Protection of Conscience Project
Protection of Conscience Project
Service, not Servitude

Service, not Servitude

Scientific and Philosophical Expertise: An Evaluation of the Arguments on "Personhood"

Linacre Quarterly February 1993, 60:1:18-46
[Edited, September 20, 1996]
(Reproduced with Permission)

Dianne N. Irving, M.A., Ph.D.*

All too often lately we hear or read the lament, "We just don't or can't know what a human being or a human person really is", or, "There just is no consensus or agreement on what the definition of a "human being" or a "human person" is, so why should one person's or one group's definition be preferred over any other. The definition of a "human being" or of a "human person" just cannot be objectively determined, and so must remain a relative one."

The aim of this paper is to debunk these current myths concerning the relativism of what a human being or a human person is, and to at least raise the question at the end of how these "myths" came about even at the level of scientific and philosophical professional "expertise". What I will argue is that we can and do have an objective and empirically-based definition of a human being and a human person, and that, other than conceptually, one cannot really split a human being from a human person. "Personhood" begins when the human being begins -- at fertilization.

Toward this end I will address some of the kinds of major scientific and philosophical arguments used to support the sudden appearance of "personhood" at different biological "marker events", indicating that such arguments are arbitrarily grounded on scientific data which is incorrect or misapplied; and that the philosophical claims of these arguments are arbitrarily grounded in systems of philosophy which are themselves very problematic, as any historian of philosophy well knows,1 with highly indefensible definitions of a "human being" or of a "human person." Such definitions are actually remnants of those philosophical systems in which conceptual mind/body splits are still sustained, even today. It is important to understand that the question of "personhood" is not simply restricted to some wild-eyed academic's preferred theoretical ramblings, but that the issue has now been translated into the quite practical question of whether or not these "tiny" human beings are as protected ethically, socially and legally as are more "mature" human beings. The really "burning" question is: if the early human embryo is a human being, is it also a human person?


Before addressing the specifics of the science and philosophy, some general charts are provided for an over-all view of the issues. Only a few of the major marker events will be covered, as the actual list is quite long. I refer you, however, to my own analysis of 26 arguments which goes into much greater detail.

Fig. 1 indicates some of the suggested biological marker events during embryological development -- from just before fertilization to about 14-days.2 During this period the major philosophical issues include whether the early human embryo is an individual (a prerequisite for personhood), and/or if he/she actually possesses the genetic or formal capacity of a human being or human person. It is during this period also when mass-confusion reigns on the philosophical misuse of the terms "possibility", "probability", "potentiality" and "potency". These positions are generally arguing for either the actual capacity for, or the actual exercising of either "rational attributes" or "sentience".

Daly3 represents the type of argument which claims that "personhood" begins at the time when the sperm h as penetrated the ovum. Examples of positions arguing for "fertilization" are my own, or Ashley and O'Rourke4 (although within the advocates of "fertilization", much ambiguity exists as to which point during the process of fertilization itself "personhood" begins). Suarez5 will argue for the 2-cell stage. And a great deal of the current literature consists of arguments for the 14-day stage.6 In these latter arguments a general distinction can be made between those which contain elements concerning the pre-condition for the exercising of so-called "rational attributes" -- e.g., self-awareness, self-consciousness, interaction with the environment, etc. -- and those concerning the pre-condition for sentience, or the ability to feel pain or pleasure. For those unfamiliar with philosophy, let me just point out that such distinctions -- as well as those that will follow -- are grounded in different philosophical schools of thought.

Some of the suggested biological marker events range from 14-days and after, as indicated in Fig. 2.7 During this period the major philosophical issues include: individuality, the biological substrate as the precondition for the capacity for "rational attributes", or for "sentience" -- or for the actual exercising of those capacities. The full integration of those substrates and capacities are also at issue.

As noted, writers such as Bole8 argue that individuality and ensoulment are not possible until after 2-6 weeks, whereas Singer and Wells9 argue that only after 6 weeks is sentience possible. At 8 weeksLockwood10 argues for the beginning of "personal identity", and Shea11 for that point where the brain actually controls bodily functions as a whole. Finally, there are those who focus not on the mere capacity but the actual integration and exercising of "rational attributes" and/or sentience as a condition for true personhood, such as Hare12 , Engelhardt13or Singer14.

As these and similar distinctions made between a human being and a human person are really philosophical distinctions, I have sketched the major historical philosophical sources of a mind/body split in Fig. 3 (although one could go back to Plato and beyond).15 The major point I want to indicate is that some philosophical schools of thought define a human being as one whole substance, and thus there is no mind/body split inherent in their theories. Such theories define a human being in terms of the actual nature of the human substance. Characteristics such as "rational attributes", sentience, moral autonomy, etc., are only activities of powers which are of secondary consideration, because they are consequent to or follow upon the actual nature of that substance.16 Other "schools" do maintain a mind/body split inherent in their theories; a human being is defined as two independent and separate substances. Interestingly, most of the theories addressed here are derivative of these modern philosophies, especially that of Descartes.17

An entire paper -- or even a book -- could be dedicated to explaining the theoretical and practical consequences of such mind/body splits, especially in the present context. Suffice it to point out that where there is such a split -- where the mind (or even the whole "soul") is an independent substance in and of itself, separate or apart from the "body" (which is seen as an independent and separate substance in and of itself) --, then it is impossible either theoretically or biologically to "piece them back together again", as Humpty Dumpty might have said. Nor could one explain any interaction between these separate "substances" of mind and body. We can see the effect of such Cartesian dualism -- and the consequent historical breaking-off to either rationalism or empiricism -- in the distinctions writers make here between a human being and a human person.


There are enumerable points along the continuum of embryological development at which different writers claim the appearance of so-called "personhood". These are claimed as "biological marker events of personhood" -- before which there is only a human being (at best); and after which there is a human person. Before that biological point, then, the human embryo or human fetus is considered as only an "object", a "thing" which may be used or dealt with according to the personal objectives or desires of a human person. After that particular biological marker event we suddenly have a human person, who is now considered a "subject" or an entity deserving of protections against the interests, objectives or desires of another human person.

A. Fertilization as the beginning of personhood

In order to identify the major issue quickly, a few questions might be posed so as to clarify at the start exactly what is at stake when we define a human being or a human person in one way or another. If our definition is incorrect -- even in part -- then the consequences of this incorrect definition are long-ranged and potentially profound. Aristotle reminds us of something we all know too well. To paraphrase him: a small error in the beginning leads to a multitude of errors in the end.18 In this case, if one's definition of a human person is incorrect, then one might find one's self experimenting on or euthanizing something which one thought was not a human being or a human person -- but which in fact really is.

So I pose the question -- how would you yourself define a human person? Would you consider any of the following a human person: a rock; a head of cabbage; a giraffe; ...those who are old and senile in a nursing home; Alzheimer's patients; Parkinsonian patients; stroke victims; comatose patients; drunks and alcoholics; drug addicts; the homeless, poor; prisoners; the emotionally ill and depressed; mothers-in-law; teenagers; the physically handicapped; the mentally ill; children under 7 years of age; a new-born baby; the fetus before the mother has given birth (or, at 6 months, 8 weeks, 35 days, 14 days, 6 days, 2 days, fertilization, or the egg or the sperm). These latter examples actually constitute some of the different biological markers at which various writers variously claim that there is present a human person. Obviously there is some disagreement about exactly when we have, definitionally, a human person present. And that period of time between fertilization and 14 days is the grayest area, i.e., the seemingly most difficult and most controversial stage.

What, then is a human being or person -- and when does he or she begin? I will argue that at the biological marker of fertilization a substantial change (or a change in natures) has taken place -- and a new, unique, living, individual embryonic human being who is simultaneously a human person is present. I will also argue that from fertilization onward -- including the zero to 14-day old embryonic human stage -- until the death of the adult organism -- accidental change (or a change only in accidents) has taken place, in which a human being/person is continuously present.19

1. The connection between science and philosophy

First, although a question about "natures" seems to be fundamentally a philosophical one, I would argue that any philosophical reflections, analyses or accounts about the nature of a human being or person must begin or start with the empirically observable biological facts.20 Otherwise our philosophical concepts actually bear little or no relation or resemblance to the real world which we are trying to understand and explain by those philosophical concepts. Instead, I would suggest, we are left with multiple half-truths or fantasies -- or wishful thinking! Epistemologically, the starting point of our philosophical questions and investigations about reality must be grounded in that empirical and scientific reality. Only in this way can we have a realistic or objectively-based definition of a human being -- one that is not relativistic.

Operationally, what is the connection between a thing's nature and the biological facts? Put briefly, the answer is that we can know what a thing is (i.e., its nature) by observing its actions and functions -- how it behaves, what it does. We know that a thing acts according to the kind of thing it is, i.e., its nature. That is simply an empirically observable fact. In first-year chemistry or in microbiology students are given "unknowns", the nature of which they must identify by means of the kinds of actions or reactions exhibited by these "unknowns" as observed in the lab. Indeed, this is the obvious principle behind any basic or experimental research. The research biologist first observes the actions, reactions, functions of a biological entity and reasons from these specific kinds of actions back to the specific kind of nature it possesses. It is this nature which directs and causes such characteristic actions. As biology texts themselves discuss it: function follows form.21 Thus Na burns orange, and cobalt burns blue/green -or beta-hemolytic streptococcus can only be grown on specific culture medium containing blood, but not on other mediums. Further, a thing is not only characterized by its nature, which determines the specific kinds of actions it can do -- but that same nature limits the kinds of actions it can do. That is, there are certain actions which a thing can not do because it does not have the specific kind of nature it would need to do it. For example, birds have wings and so can fly -- but stones, dogs or human beings can't fly; corn stalks produce ears of corn and corn proteins and corn enzymes -- but acorns, tomato plants or asteroids do not and cannot produce corn or corn proteins. Frog embryos direct the formation of frog tissues and organs -- but they cannot direct the formation of human tissues and organs.

Apply these considerations to the point at hand. To determine what a human being or person is is really not all so difficult as is often claimed. We are not Gods or angels -- but embodied human beings.22 We do have bodies -- don't we? At least I have never seen a simple "soul" wandering aimlessly around the labs, manipulating a computer, cooking dinner or playing soccer without a body. In fact, I have never seen even a Platonic or a Cartesian philosopher "thinking" without his or her body! As Aristotle noted, the whole man thinks; the whole man knows; and the whole man acts.23 There are voluminous biological facts which we do know already about the human body and its embryological development. Clearly by observing and studying these known biological facts -- how the human being begins his or her biological existence as a specifically human zygote, and the kinds of specifically human functions and human actions that take place during embryological development -- we can then determine to a very sophisticated extent the nature of a human being or a human embryo -- or "what" it is. So I will turn now to a brief consideration of the well-known, well-referenced biological facts concerning when the life of a human being begins to exist and how it then merely grows and develops during embryogenesis, without changing "natures".

2. The scientific facts

Before fertilization there exist a human sperm (containing 23 chromosomes) and a human ovum (also containing 23 chromosomes -- the same number, but different kinds of chromosomes).24 Neither the sperm nor the ovum, singly, by itself, can become a human being -- even if implanted in the womb of the mother. They are only gametes -- they are not human embryos or human beings. In contrast, the single-cell embryonic human zygote formed after fertilization (the beginning of the human being and the embryonic period)25 contains 46 chromosomes (the number of chromosomes which is specific for members of the human species) -- and these 46 chromosomes are mixed differently from the 46 chromosomes as found in either the mother or the father -- that is, they are unique for that human individual. And at the single-cell embryonic human zygote stage that unique individual human being is already genetically a girl or a boy.26 If allowed to "do his or her own thing", so to speak, this embryonic human zygote will biologically develop continuously without any biological interruptions, or gaps, throughout the embryonic, fetal, neo-natal, childhood and adulthood stages -- until the death of the organism. And with the advent ofin vitro fertilization techniques, we can see that the early human embryo can develop in vitro on his or her own without the nutrition or protection of the mother for quite a while -- someday, perhaps, even until "birth"!

I want to reiterate that a human gamete is not a human being or a human person. The number of chromosomes is only 23; it only acts or functions biologically as an ovum or as a sperm, e.g., it only makes ovum or sperm enzymes and proteins, etc., not specifically human enzymes and proteins; and by itself it does not have the actual nature or potency yet to develop into a human embryo, fetus, child, or adult. And in that sense gametes are only possible human beings (i.e., human beings who do not exist as yet). Only after the sperm and the ovum chromosomes combine properly and completely do we have a human being. Individually, the nature of a sperm is different from the nature of an ovum -- and both are different from the nature of the embryonic human zygote which is formed when their chromosomes combine.

Thus from perhaps an Aristotle-the-biologist's point of view, one would say that before fertilization there are two natures -- i.e., the nature of an ovum and the nature of a sperm. After fertilization there is a human zygote with one nature, i.e., the nature of a human being. Thus, in fertilization there is substantial change,27 (i.e., a change in substance or nature -- or "what" it is). The substances or natures of the ovum and the sperm have changed into the nature of a human being. This is, in fact, known empirically by observing the number and kinds of chromosomes present before and after fertilization, and by empirically observing the different characteristically specific actions and functions of the ovum, the sperm, and the human zygote. Once fertilization has taken place and the new human being has formed, only accidentalchange28 occurs (e.g., a change in weight, height, size, shape, etc.), and we know this empirically as well. We can observe that the nature of the human being does not change (e.g., into a cabbage or a giraffe), only its human accidents change.

Thus embryological development does not entail substantial change, but only accidental change. Once it is a human being it stays a human being, and acts and functions biologically as a human being. The human zygote produces specifically human enzymes and proteins; he or she forms specifically human tissues and organ systems, and develops humanly continuously from the stage of a single-cell human zygotic embryo to the stage of a human adult.29

This is observed empirically. A human zygote does not produce cabbage or carrot enzymes or proteins, and does not develop into a rock, an ear of corn, nor into a cat, a horse, a chicken, or a giraffe. Empirically it is observed that a human zygote produces specifically and characteristically human proteins and enzymes at the moment of fertilization -- as demonstrated recently, for example, by experiments using transgenic mice30 -- and that he or she develops continuously throughout embryological development in a specifically and characteristically human way.

In short -- the biological facts demonstrate that at fertilization we have a real human being with a truly human nature. It is not that he or she will become a human being -- he or she already is a human being. We know that empirically. And this nature or capacity to act in a certain characteristic way is called, philosophically, a nature or a potency.31 Thus a human zygote or embryo is not a possible human being;32 nor is he or she a potential human being;33 he or she is already a human being. A human zygote, embryo or fetus does not have the potency to become a human being, but already possesses the nature or capacity to be at that moment a human being. And that nature will direct the accidental development, i.e., the embryological development, of his or her own self from the most immature stage of a human being to the most mature stage of a human being.

Now, this is strongly convincing empirical evidence that at fertilization there is present a human being (the well-referenced unequivocally agreed upon answer to the scientific question); but is there also a human person (a philosophical question) -- or not? These are two different questions -- one scientific, the other philosophical. It is in this shifting from the paradigm of a human being to that of a human person where the philosophy -- and the confusion -- come into play. Is a human being also a human person; or are they different things? Which philosophy is adequate to cope with this biological data?

3. The matching philosophical concepts

(Fig. 3) With even only a cursory rummaging through the history of philosophy, there is one major "realistic" philosophical "ball-park" which would in fact deny that there was any real (as opposed to conceptual) essential distinction between a human being and a human person. That is, in the real world which we experience empirically, they cannot really be split or separated -- except perhaps only conceptually. This philosophy was part of a 2500 year old tradition which was the bath water, so to speak, that was "thrown out with the baby". It is the philosophical ball-park, for example, of Aristotle-the-biologist.34 For Aristotle -- as well as for others, such as Thomas Aquinas -- his major metaphysical and anthropological treatises argue consistently for a single human substance with no mind/body split (although there is evidence of a serious Platonic streak in his De Anima -- that atypical and historically problematic treatise of Aristotle's so often quoted by contemporary scholars -- as well as historians who researched for Roe vs Wade). As Aristotle argues:

"...'nature' has two senses -- matter and form. If one considers 'nature' as the form, then it would be the shape or form (not separate except in statement) of things which have in themselves a source of motion"35 (emphasis added).

Again, he says:

..."the physicist is concerned only with things whose forms are separable [in the mind], indeed, but do not exist apart from matter."36

And similarly, matter cannot exist apart from the form. For Aristotle, the human being is defined as one composite substance -- the vegetative, sensitive and rational powers of the "soul" together with the human "body".37 The whole soul, he wrote, is homogenous, and in each part of the body as one whole composite:

In each of the bodily parts there are present all the parts of the soul, and the souls so present are homogenous with one another and with the whole; this means that the several parts of the soul are indisseverable from one another.38(emphasis added)

And in contrast to his opposite view in the very same De Anima, Aristotle addresses the very possibility of a "being-on-the-way", or an "intermediate" human being, railing against the anthropological consequences of Plato's or Pythagoras' mind/body split when he very sarcastically retorts: "Yet how are we to believe in such things?" (emphasis in the original).39 Although Aristotle-proper did not actually use the term "person", he clearly would have to concur that a human being is always a human person, for neither form nor matter can exist on their own as two different things or independent substances.

Thomas Aquinas, to give another example, puts an even finer gloss on Aristotle's anthropology, by affirming his own adamant rejection of Plato's anthropology. To paraphrase Thomas: the name of "person"(and he uses that term) does not belong to the rational part of the soul, nor to the whole soul alone -- but to the entire human substance (or, subsistens).40 This means that the whole soul, whole body and its act of existing constitute one substance entire -- with no separate and troublesome independent "parts" each of which are claimed to be true and independent whole substances. And it is worth noting that Aquinas is one of the only philosophers whoincludes undesignated matter in his formal definitions of natural things -- of which man is one.41

For Thomas a human being is a human person, and the later characteristics which we will look at in these debates, such as "rational attributes", autonomous willing or sentience, are only consequential and secondary or accidental actions which follow upon certain powers (not "parts") which themselves follow upon the essential nature of the human being itself.42 That nature is defined as the single, whole, formal, material and existential human substance. As Thomas states:

...the soul must be in the whole body [and therefore not just in the brain], and in each part thereof ...for to the nature of the species belongs what the definition signifies; and in natural things, the definition does not signify the form only, but the form and the it belongs to the notion of man [defini [definition] to be composed of soul, flesh and bones.43(emphasis added)

These philosophical precisions force at least two major questions on any of the several types of Aristotlean/Thomistic frameworks used in these debates. First, if it is claimed that the "rational" soul -- which "organizes and directs embryological development" -- is not infused until about the third month,44then what explains the specifically human organization of the human embryo and human fetus up to that point? Hasn't the work of this supposed "delayed rational soul" already been done -- as empirically verified? If so, then this biological evidence of specifically human organization which we do empirically observe must be accounted for by the presence of the human soul right from the beginning. In addition to the specifically human structural organization from the beginning, we also empirically observe specifically human functions and activities from the beginning -- e.g., the production of specifically human proteins, enzymes, etc. If so, then this biological evidence of specifically human functions and activities which we do empirically observe must be accounted for by the presence of the human soul right from the beginning.

Second, for both Aristotle and Thomas the "rational soul", or more properly, power, includes virtually the veg the vegetative and sensitive powers,45 and for neither is there such a thing as a "rational soul" alone, or even a whole soul alone -- or a whole soul without a body (except in some sections of the De Anima). The whole existing human complex (body and soul -- and for Thomas, esse) must be present together at once.

Apart from the biological and conceptual absurdity of an "intermediate man" walking down the street, if there were only a "vegetative" soul present at first, how do we explain the production of specifically human enzymes and proteins -- instead of carrot or corn enzymes -- from the very start? If there were only a "vegetative and sensitive" soul present, how do we explain the production of specifically human tissue and organs -- instead of only giraffe or gorilla organs and systems? If the human soul cannot be split (and must contain all three powers at once), and if specifically human enzymes, proteins, tissues, organs and structures are empirically observed -- which they are -- then the human rational soul must be present at the very beginning along with the human vegetative and sensitive "powers" (not "parts") of the human soul. And this "soul" -- or, more properly, these powers -- must exist as a composite with the human body which it is organizing and whose functions and activities it is directing from the moment of fertilization -- which we know empirically.

Thus, atThus, at fertilization, I would argue, the "matter" (i.e., the newly combined fertilized ovum or embryonic single-cell zygote) is already appropriately organized as human -- since we empirically observe it as specifically human and as developing humanly from the beginning.46

So far the scientific facts and the philosophical concepts match. At this point I want to take a closer look at the biological facts after fertilization, i.e., those of human embryological growth and development. Along the way I will point out several other different biological "marker events" of personhood which have been variously argued by others. All of these writers will make a real distinction between a human being and a human person -- supposedly based on these biological marker events. The use of certain biological data which they will use to support their arguments will also be addressed. (The use of their problematic philosophies with mind/body splits, which seem to be imposed upon their problematic biological facts, will be discussed later in this paper).

B. Zero - 14-days

As noted above, the newly formed single-cell embryonic human zygote consists of 46 chromosomes and non-nuclear DNA in which are coded the specific directions for virtually all of the processes of embryological development. The content of this initial pool of genetic information never changes throughout embryological development.

(1) Yet (1) Yet it has been argued by Bedate, Cefalo47 and Bole,48 for example (Fig. 1), that not all of the "information" needed is present in this single original cell, that some of the information comes from "molecular information" in later stages of development, and some even comes from "molecules" originating from the mother. Thus they conclude that the original human zygote does not contain all of the "information" needed to be a self-directing, human individual, and therefore it is not a human person.

I would question this biological data. First, "molecular information" or "positional information" is not the same as genetic (chromosomal) information. Yet they seem to gloss over this very important scientific distinction, and imply that the two are the same. Second, "molecular information" itself is coded in the original single-cell human zygote. As the embryologist Moore discusses at great length, the genetic information in the original human zygote determines what "molecular information" will be formed, which in turn determine what proteins and enzymes will be formed, which determine which tissues and organs will be formed. In genetics this is called the "ding" effect.49 That is, the information in the original single-cell embryonic human zygote "cascades" throughout embryological development -- each previous direction causing the specific formation of each succeeding direction. Thus, all "positional" or "molecular" information or direction is already determined itself by the information which preceded it, and ultimately by the original genetic information in the single-cell human zygote.50

Third, although the genetic information in the human zygote may direct the absorption of molecules from the mother, that hardly means that the maternal molecules or the mother herself determines the very nature of the growing embryo or fetus which she is merely nurturing. (This argument is also rejected by Suarez51). The nature of the embryo or fetus, as is empirically known, is determined by the formal biological genetic make-up of the zygote from which he or she continuously develops; and the directing of this absorption of maternal molecules is done by the genetic information within the embryo or fetus -- not by the mother or any genetic or "molecular" information from the mother.52 Those are simply the correct biological facts. As Jerome Lejeune, the internationally prominent prize winning geneticist has testified:

... [E]ach of us has a unique beginning, the moment of conception... As soon as the twenty three chromosomes carried by the sperm encounter the twenty-three chromosomes carried by the ovum, the whole information necessary and sufficient to spell out all the characteristics of the new being is gathered... (W)hen this information carried by the sperm and by the ovum has encountered each other, then a new human being is defined which has never occurred before and will never occur again.... [the zygote, and the cells produced in the succeeding divisions] is not just simply a non-descript cell, or a "population" or loose "collection" of cells, but a very specialized individual, i.e., someone who will build himself according to his own rule."53 (emphasis added)

Finally, Bedate and Cefalo54 also argue that the developing embryo can give rise to biological entities which are not human beings, e.g., hydatidiform moles and teratomas. But hydatidiform moles and teratomas do not arise from genetically normal human embryos, but from abnormal entities (usually caused, e.g., by dispermy), which are not therefore genetically normal human beings to begin with.55

Again, he says:

(2) Next, it is argued by some that this original single cell divides neatly first into 2 cells, then into 4 cells, then into 8 cells, etc.56

This biological data too is questionable, (and has consequences in understanding the argument about "totipotency"). As known and published in human embryology textbooks for over 60 years (as Lejeune57 points out), human embryogenesis immediately following fertilization is asynchronous (unlike amphibian or mouse embryology). The original single cell divides into 2 cells -- and then only one of those cells divides, giving 3 cells . After a time the other cell divides, making it 4 cells, and then 8 cells, etc.

Part of what happens at this three-cell stage is that one can observe empirically the process of methylation. This observation is important philosophically. Many argue that these very early cells -- including the original single-cell zygote up to the 8-cell stage -- are "totipotent".58 They explain totipotent cells as the most vaguely directed and least differentiated cells in all of embryological development. Each cell, they claim, is not yet determined enough to be classified as an individual human being or a part of an individual human being. These cells, they say, have not yet "made up their minds" what they want to be. They can become any number of things. These cells are not differentiated or specialized enough yet. What happens in early development, they claim, is that there is a gradual change from total unspecialization to greater and greater specialization or differentiation. For example, at first we have a cell that could become any kind of human cell. Progressively a cell becomes specialized so that it can only become a kidney cell, or a stomach cell, or a muscle cell, i.e., it becomes more and more determined and differentiated.

This portrayal of differentiation is backwards, as Lejeune notes. The original single-cell human zygote is the most determined and specialized cell in all of embryological development. Progressively he or she loses, in fact, the ability to use information. A kidney cell, for example, contains virtually all of the genetic information that was in the original single human zygote cell, but can now use only a small portion of that information. So the kidney cell has not lost any of this information -- only the ability to use it. This ability to use or not use the information that is present is partially determined by the process of methylation (which itself is coded in the original single-cell zygote). Through methylation and other processes during embryogenesis, genes are turned on or turned off. When the cell wants to control the use of cellular information, it methylates a molecule to silence that gene, to block or stop its use at a certain point in development. No information is progressively lost; only its use is lost. Thus a specialized kidney cell cannot be prodded to become an entirely new human being -- not because it does not have all of the necessary information (it does), but because all of the information other than that of being a "kidney cell" has been methylated, or silenced.59

Thus to be so differentiated as a kidney cell is actually a negative in such arguments. The kidney cell cannot direct anything but a small minuscule part of the development of the human embryo or fetus; whereas the original single-cell human zygote contains and can use all of the genetic information only partially used by the later cells. So there is nothing vague, undirected or undecided about it. It is the human zygote which represents the greatest fullness of human content and useable information, of directedness and decisive action -- more than that found in any of the later cells. The human zygote will "decide" what reactions and formations take place. He or she will direct all of the processes and formations during the entire embryological process.60 Furthermore, "totipotency" is even suppose to happen -- it is a normal part of human embryogenesis, and is indeed encoded in the original genetic information of the human zygote. Differentiation is also encoded in the original human zygote, and is partly explained by methylation. Differentiation, then, really represents the restricted ability to make any "decisions".

(3) Next, Suarez argues for the 2-cell stage, with, as he claims, the completion of the first division and of the genetic input. "The two-cell stage already is, like the adult, a moment in the execution of the program 'man'". And besides, he argues, the two-cell stage is already the same living being as the human adult arising from it.61 However, we already know that the genetic input is complete at the single-cell zygote stage, and that the zygote in fact is the source of the genetic input of the two-cell stage and is the same living being as both the two-cell stage and the adult stage. Thus Suarez's own argument actually argues for personhood for the zygote rather than for his two-cell stage.

(4) But to continue, the cells will proceed to divide until about 5 or 6 days, when two cell layers are formed in the blastocyst -- the trophoblast or outer cell layer, and the embryoblast or inner cell layer. Some writers, such as Grobstein and McCormick, have stated that this stage is significant because they can demonstrate empirically that there can be no true human individual present at this time -- we have only a genetic individual, not a developmental individual. A person can be present, they claim, only if there is a developmental individual -- and this cannot take place until 14-days:

I contend in this paper that the moral status -- and specifically the controversial issue of personhood is related to the attainment of developmental individuality (being the source of one individual)... It should be noted that at the zygote stage the genetic individual is not yet developmentally single -- a source of only one individual. As we will see, that does not occur until a single body axis has begun to form, near the end of the second week post fertilization when implantation is underway.62 (emphasis added)

It is to be noted that the moral status of the developing human being explicitly hinges directly on what developmental stage he or she is at. Note also that they make implantation (5-7 days) co-extensive with two weeks (when the primitive streak begins to form) -- also scientifically incorrect.

But to continue, these early cells, they claim, are only "collections" of undifferentiated, "totipotent" cells, and they name them, or designate them collectively, as only comprising a "pre-embryo" (a term, by the way, which is specifically rejected by human embryologists63 -- only amphibian and mouse embryologists, philosophers, theologians and bioethicists use the term). Further, the term was rejected by the judge in the Davis vs Davis frozen embryo case.

The scientific facts which they give to support these claims are the following. They claim that only the cells from the inner layer of the blastocyst (the embryoblast), eventually become the adult human being. The cells from the outer trophoblast layer, they write, are all discarded after birth as the sac and the umbilical cord, etc. Thus, developmentally, the implication is, that we are not dealing exclusively with those "important cells" which will become the adult human being, i.e., the embryoblast, but rather a mixture of "essential" and "non-essential" cells, i.e., a PRE-embryo. A pre-embryo, then, is not a human person, yet:

This multicellular entity, called a blastocyst, has an outer cellular wall, a central fluid-filled cavity and a small gathering of cells at one end known as the inner cell mass. Developmental studies show that the cells of the outer wall become the trophoblast (feeding layer) and are precursors to the later placenta. Ultimately, all these cells are discarded at birth64(emphasis added)

But, again, these scientific "facts" are questionable, and necessarily lead to questionable philosophical concepts. It simply is not true that all of the cells from the trophoblast layer are discarded after birth and do not contribute cells to the inner cell layer; nor is it true that only the cells from the inner layer become the later adult or that none of the cells from the inner cell layer contribute to the outer layer. As can be found in virtually all embryology texts, including Moore's text from which they quote, many of the cells from this trophoblast layer become an integral and essential part of the constitution of the later fetus, newborn and adult human being. For example, the cells from the trophoblast layer known as the yolk sac cells become part of the adult gut. And cells known as the allantois cells become part of the adult ligaments, blood cells and urinary bladder.65

Thus these "scientific" facts used by Grobstein and McCormick are scientifically incorrect -- and therefore so also are their philosophical conclusions about "pre-embryos" and "developmental individuals" which are grounded on those incorrect scientific facts.

Yet McCormick and Grobstein continue. It is impossible, they claim, for a human person to be present until at least the 14-day marker event, at which point the primitive streak forms in the embryo. The philosophical significance of this marker, it is claimed, is that until the formation of the primitive streak it is possible for twinning to take place. The totipotent cells "do not yet know whether to be one or two individuals". After 14-days, they claim, twinning is not possible, and thus the organism is finally determinately developmentally one individual -- an essential pre-requisite for personhood.66

But, again, this science is incorrect. As Karen Dawson67points out in these debates -- and as is found in every human genetics textbook -- it is possible for monozygotic twinning to take place after 14-days and the formation of the primitive streak. For example, fetus-in-fetu twins can be formed up to 2 and 3 months after fertilization, and Siamese twins even later. Also, it is known that "twinning" is sometimes genetically determined and coded in the original human single-cell zygote (as, indeed, is totipotency and differentiation).

There is nothing magical, it turns out, about this 14-day stage as far as the concept of individuality and personhood is concerned. (Even the Warnock Report, which encouraged the use of the term "pre-embryo", admitted that the 14-day marker event or any other was totally arbitrary, as did the NIH Human Embryo Research Panel).68 If a 2-cell, 8-cell, implantation stage, 14-day primitive streak stage embryo or 4 month fetus splits into twins, that simply means that the original entity was one individual -- and now there are simply two individuals. The fact of twinning says nothing about the individuality of the first individual, i.e., the single-cell human zygote.69 Indeed, the history of all living organisms is of one individual giving rise to another individual -- but one would certainly not then conclude that there were therefore no individuals ever present, or that the former individual was hopelessly "undecided".

C. Ward Kischer, a human embryologist, argues that the scientific data of McCormick and Grobstein is highly selective and that they leave out a majority of other relevant data:

It is not a question as to whether science can or cannot decide the question of personhood. Science is not interested in deciding personhood. However, if the socio-legal status of personhood cannot be decided without invoking what is known scientifically, then the whole of scientific data should be used and not arbitrarily selected bits and pieces of data. (emphasis in original)

... Human embryology is now in danger of being rewritten as a stratagem statement of current socio-legal, but also of late, even theological issues. Unless the errors are corrected now, we will be in danger of entering a protracted period of false concepts concerning our own development.70

Unfortunately, Grobstein later publicly admitted before a scientific conference that he had knowingly substituted amphibian embryology for human embryology.71 Yet this "science" continues to be promoted. For example, there are the claims by Robertson (a lawyer) that "personhood" is only a social construct and that the early human embryo has only "symbolic value" to the parents and society.72 But Robertson bases his argument almost exclusively and exhaustively on the "embryology" of Grobstein, even in his court cases. And recently, the N.I.H. Human Embryo Research Panel issued its Recommendations to the Director of N.I.H. Ron Greene and Carol Tauer, the Ethics Co-Chairpersons of that Panel, grounded the "reduced moral status" of the early human embryo on the published work of Grobstein and McCormick, and most of the writers considered here73 -- concluding that certain kinds of destructive experimental research could ethically be performed on these early live human embryos because of their "reduced moral status".

Furthermore, certain pharmaceutical companies have argued that the F.D.A. should allow them to market oral contraceptives because there is "no embryo there until two weeks", and therefore their product is not abortifacient. Their source for this scientific claim is the Australian theologian Fr. Norman Ford's book (below), grounded on the "science" of Grobstein and McCormick.74 Obviously, if Grobstein's embryology is incorrect, then Robertson's argument, the N.I.H.'s Recommendations, and the claims by the pharmaceutical industry and advocates which are all based on Grobstein's "embryology" are also invalid.

(5)Ford75 also argues for the 14-day stage, based primarily on the same science from Grobstein, although Ford claims there is an individual present at fertilization -- but it is only a biological individual. Rational ensoulment cannot take place until after 14 days, at which point there is, he claims, an ontological individual, i.e., when differentiation is completed and there is a distinct individuality.76But aside from the problems with the science of Grobstein and McCormick on which Ford basis his own conclusions, we know empirically that complete differentiation does not actually take place until well after birth. As the embryologist Moore states:

Human development is a continuous process that begins when an ovum from a female is fertilized by a sperm from a male. Growth and differentiation transform the zygote, a single cell formed by the union of the ovum and the sperm, into a multicellular adult human being. Most developmental changes occur during the embryonic and the fetal periods, but important changes also occur during the other periods of development: childhood, adolescence, and adulthood... Although it is customary to divide development into prenatal and postnatal periods, it is important to realize that birth is merely a dramatic event during development resulting in a distinct change in environment. Development does not stop at birth: important developmental changes, in addition to growth, occur after birth... Most developmental changes are completed by the age of 25.77(emphasis added)

Obviously, then, a 14-day embryo is nowhere near being "completely differentiated". Once again, the incorrect science on which a philosophical claim is based actually negates the validity of that philosophical claim.

C. After 14-days

(1) Sometimes Wallace,78 too, wants to argue for 14-days, but he is inconsistent and seems more to argue for a point after 14-days. He bases his own position on what he calls an "Aristotelean-Thomistic" theory of "natural law". This "natural law theory" grounds his distinction between transient natures (or seeds, or beings-on-the-way) as applied dubiously and analogously to the transition from plant, animal, to human natures during human embryological development; and stable natures, as applied to the actual embryological development of individual systems of plants, animals and human beings. This "transition" from plant, animal to human substances during human embryological development for Wallace is, then, actually a series of substantial changes within human embryogenesis itself; and once again he bases much of his argument on the science of Grobstein and McCormick, and a rather neo-Platonic rendition of Aristotle and Aquinas, as well as a distinctively physicist's rendition of "science".

Two points out of many which are problematic are his descriptions of his "Aristotelean-Thomistic" grounding, and the blatant contradictions in his analogies. First, Wallace subscribes to the Aristotle of the historically problematic De Anima, and attributes to both Aristotle and Thomas a theory of the "eduction" of these substantial forms from "proto-matter", substantial forms which Aristotle, he says, would call "natures", and which Thomas, he says, would define as (quantity + proto-matter) -- a definition of substance with which neither Aristotle-proper nor Thomas would agree. Wallace renames this as "mass-energy", to bring Aristotle and Thomas "up to date with modern physics".79

However, Wallace is really elucidating a very neo-Platonic interpretation of both Aristotle and Thomas, one with which neither the historic Aristotle nor Thomas can be reconciled. Neither of them gave any real existence to "proto-matter", or what I think Wallace confuses with "prime matter". And, indeed, for both of them "prime matter" was only a conceptual construct, and by definition, was totally without forms80-- in fact, that was the whole point! As Klubertanz states:

Of itself, prime matter is not actually any kind of thing; nor does it have quantity, or any kind of qualities or other accidents. Hence prime matter cannot exist in itself; it cannot be found as such in direct or indirect sense experience; it cannot even be understood separately from substance or substantial form. It is an intelligible co-principle...81(emphasis added)

Thus no substantial forms can be educed from "proto-matter" for either Aristotle or Thomas, because there were no forms there to begin with. And Thomas, like Aristotle, actually argued against this sort of theory:

Creation does not mean the building up of a composite thing from pre-existing principles; but it means that the composite is created so that it is brought into being at the same time with all its principles.82(emphasis added)

Further, "quantity" for both Aristotle and Thomas was an accident of substance, not a concrete substance itself.83 Thus neither would even equate their "quantity" with the modern concept of "mass". And finally, Wallace also never once includes esse (the act of existing) -- which is the hallmark of Thomas' definition of any existing substance -- in any of the definitions of "substance" which he attributes to Thomas. In fact, he simply never mentions esse at all.

Second, his concept of "transient natures" is drawn from rather shaky chemistry and biology. He claims, for example, that when Na and Cl react together they each actually change their natures. But Na and Cl are only sharing electrons, not protons (which determine the "nature" or kind of element it is, and which place the element in a specific place in the periodic chart). He also fails to mark the critical differences between the nuclei of radio-isotopes and those of living cells. Nor does he mark the critical differences which distinguish the generation of a radioisotope from that of a plant; nor that of an animal from that of a human being. He also builds a "model" of what he calls "transient natures", yet admits that they probably are really "stable natures"! Inexplicably he will call them "transient natures" anyway.84 He then applies his own theory of transient natures, questionable even to himself -to plant and animal generation -- all the while acknowledging that real plants and real animals have stable natures which are descriptive of the mature individuals only -- not to the developmental stages of those individuals.85 How credible is such a theory? Should it be applied to determine the real moral status of real live human beings?

(2) A final marker event I will point out is 8 weeks or several time-markers after that (Fig. 2) -- although there are many others with equally troubling science invoked. Personhood, it is claimed, does not begin until the dawning of or the maturation of the physical substrate of human consciousness, self-consciousness, or sentience -- i.e., the nervous system and/or the brain. Indeed, there is already a movement by some in legal jurisprudence to formalize the legal concept of "brain birth" to denote that point in time biologically when there is present a "person", as a parallel to the already legal criteria of "brain death".

One well-known criticism of this claim comes from Gareth Jones, who rejects scientific claims that we can determine the biological point of either "rational attributes" or sentience. As he states, the parallelism between brain death and brain birth is scientifically invalid. Brain death is the gradual or rapid cessation of the functions of a brain. Brain birth is the very gradual acquisition of the functions of a developing neural system. This developing neural system is not a brain. He questions, in fact, the entire assumption and asks what neurological reasons there might be for concluding that an incapacity for consciousness becomes a capacity for consciousness once this point is passed. Jones continues that the alleged symmetry is not as strong as is sometimes assumed, and that it has yet to be provided with a firm biological base.86 A different Jones who is partaking in these debates makes the following poignant remark:

The reproductive biologist cannot assign moral status to the sperm or the egg or the fertilized egg or any of the subsequent products that may result from this fusion ... The reproductive biologist can help, however, by assuring that other scientists or those who wish to assert a moral status, and use a biological term or concept to do so, know what they are talking about!87(emphasis added)

Furthermore, the empirical fact is that complete physiological brain integration is not complete until many months or years after birth,88 just as the complete exercising of "rational attributes" is not possible until years after birth.89 Empirically this would extend their biological marker for personhood into early adulthood (and thus the moral status as well).


I could continue, biologically, down any number of "marker events" where it is argued at different points during biological development that until that point there is only a human being and only after that point there is a human person. But virtually every single marker event claimed is also using extremely problematic scientific "data" to back up their philosophical claims of personhood. It would seem that there is more of a problem here than simply the use of incorrect science. Perhaps there is also involved -- whether consciously or not -- the imposition on that incorrect science of certain characteristically problematic philosophical presuppositions. What I see is the use of specific metaphysical and anthropological presuppositions which result in a classic mind/body -- or even sometimes a body/body split -- that are imposed upon the scientific data.

A rough consideration of just how different philosophical schools of thought have defined a "human being" or a "human person", then, is in order. Especially in light of the obvious biological continuity present throughout the entire course of embryological development, as well as the specifically human development which we know empirically takes place, how adequately do the various philosophical definitions of a human person reflect the correct biological facts as we empirically know them?

I will focus on the definition that is most generally agreed upon these days, i.e., one that is basically "derived" from Descartes90or Locke.91Generally, a human person is someone who is actually acting at the time in a rational manner (Fig. 3). That is, he or she is self-conscious, self-aware, competent, autonomous, logical, mature, conversant, and interacts with the environment and other rational beings around him or her. In short, if one is acting rationally one is a person. If this is true, then 99% of the possible examples of human persons I gave you at the beginning of this paper are -- by definition -- not persons. Those examples include the mentally ill and retarded, drug and alcohol addicts, patients with Parkinson's and Alzheimer's diseases, and the comatose (medical conditions which especially affect a considerable percentage of the elderly population).

This is the sort of philosophical definition that in fact has been used for many years by writers such as Engelhardt,92Tooley,93Kuhse94and Singer95 (yes, the animal rights person) who argue in the literature for infanticide of even normal healthy infants. If, they argue, a normal new-born baby cannot act rationally (as described above), then it is not a "subject" but only an "object" -- and we can therefore use it in destructive experimental research if we rational agents so chose. In Singer's own words:

Now it must be admitted that these arguments apply to the newborn baby as much as to the fetus. A week-old baby is not a rational and self-conscious being, and there are many non-human animals whose rationality, self-consciousness, awareness, capacity to feel pain (sentience), and so on, exceed that of a human baby a week, a month, or even a year old. If the fetus does not have the same claim to life as a person, it appears that the newborn baby is of less value than the life of a pig, a dog, or a chimpanzee.96 (emphasis added)

And philosopher Richard Frey (presently a Senior Scholar at the Hastings Center), pushing Singer's logic (correctly) one step further, suggests that mentally ill human beings are therefore also not "persons", and therefore they might be used in purely destructive experimental research in place of the higher animals who are "persons".97

Would you agree that the killing of normal healthy human infants, or the substitution of mentally ill human beings for the higher animals in destructive experimental research, is morally justifiable? If not, then we have to question, at least, such very rationalistic definitions of a human person, and the metaphysical and epistemological foundations on which they are grounded. If one argues from the rationalistic premise that a "human person" is defined only in terms of active "reason" (or only the rational part of the soul), and if only normal older children or adults exhibit such active "rational attributes", then even a normal newborn infant, or a 15-year old child is not a person -- and to be logically consistent, you must agree with Singer's or Engelhardt's arguments for infanticide, and with Frey's conclusions about the mentally ill in research. To be even more logically consistent, you might also have to agree that my partial list of human beings who are not presently exercising their "rational attributes" could also be used for the "greater good" in experimental research, be denied medical help or costs, or be euthanized.98 After all, these populations of human beings have a "reduced moral status" -- they are no longer human persons -- no longer "subjects", but "objects".99

On the other hand, sometimes a "human person" is defined only in terms of the whole soul -- i.e., the vegetative, sensitive and rational "souls" all together. Once this soul unites with a body, we then have a human person. It doesn't matter, they say, whether this person is presently acting rationally. What is important is that the rational nature or capacity is present. But if we think about it, we run into similar problems as mentioned earlier. If there are no vegetative, sensitive, or rational directions injected until about 3 months -- how did a specifically human biochemical, tissue, organ system get built before 3 months?

Or perhaps we should restrict ourselves to a purely material definition of a "human person". The human person is simply a complex system of molecules, tissues and organs. But this definition has continuously failed in explaining our experience of thoughts, ideas, and concepts, and especially of intentionality, willing, or choosing. It is argued that a "person" is simply a more advanced sophisticated phase of a material complex human being. But aren't we really talking then about a secondary or accidental quality? Surely the definition of the nature of a human person should not be put in terms of only a secondary or accidental phase -- however sophisticated it may be. And again, if you are arguing from the materialist premise that a "human person" is defined only in terms of sentience, or the physical integration or functioning of the brain, then you will also have to argue for infanticide -- or worse (as already indicated), because as pointed out, full brain integration and sentience is also not completed until over the age of 20 years, and paraplegics, stroke victims, advanced diabetics, and the comatose often cannot optimally feel pain.

Finally, there are some who would follow the long-discredited "scientific" theory that any individual instance of embryogenesis "recapitulates" the historical evolution of the species (e.g., that there is the formation of ancestral "gills" or "tails" during the embryogenesis of a single human embryo, somehow "recapitulating" the evolution of all of the species). Such "theories" are still attractive, especially to evolutionists, and to some "process" philosophers and theologians -- leading again to a theory of delayed hominization.

However, these claims were based on scientific myths (the best they could do at the time) which have long since been discarded scientifically. There is no empirical evidence that the "gills" or "tails" of primitive animals are really formed during any individual embryogenesis of a single human embryo, and such theories are rejected (if discussed at all) even in human embryology text books. Such claims fail to make a real distinction between the historical process of the evolution of millions of different species (which takes place over millions of years) and the mere growth and development of a single individual human being within one species (which takes only nine months). In short, it confuses a "species" with an individual. As O'Rahilly succinctly puts it:

The theory that successive stages of individual development (ontogeny) correspond with ("recapitulate") successive adult ancestors in the line of evolutionary descent (phylogeny) became popular in the 19th century as the so-called biogenetic law. This theory of recapitulation, however, has had a "regrettable influence on the progress of embryology" [citing de Beer]... Furthermore, during its development an animal departs more and more from the form of other animals. Indeed, the early stages in the development of an animal are not like the adult stages of other forms, but resemble only the early stages of those animals.100

Could "process" scientists, philosophers and theologians be imposing their philosophical presuppositions on the individual processes of human embryogenesis? Does every individual process imply evolution? Just because there is a process does not mean that there is no individual there or that the very nature of that individual is changing during that process. Consider the life-long process of growth and development (embryo, fetus, infant, child, adult, elderly) which any individual human being goes through. Just because there is a process taking place does not mean that there is no individual human being who retains his/her own nature throughout that process.

At any rate, if "recapitulation" were true, then we would also observe the formation of "fish" or "monkey" enzymes, proteins and tissues, which we don't. Even though there are many genes we do share in common with other species, let's not forget about the genes we do not share with them and which make us specifically human and different from them.

Once again, consider the legitimacy of the fundamental groundings on which so-called "process" scientific, philosophical or theological theories are based. Who is to say that any particular "rendition" of that "process" is either sound or valid to begin with. Can any such proponent successfully prove the validity of his or her "process" theory, or successfully defend it? Could such a "calculus" be arbitrary or abused? And once again consider the logical and practical conclusions to which one must be pushed if "moral status" is merely grounded on a "calculus of process". Literally no human beings contained within that process would be left untouched or unaffected.

The political and cultural impact of such incorrect scientific and philosophical definitions (or redefinitions) of "personhood" is potentially devastating. As Judge Robert Bork has so succinctly and brilliantly comprehended and demonstrated, such "logic", the scientific and philosophical premises on which they rest, and many of the several radical libertine and egalitarian agendas which have been derived from them, are pushing us ever more rapidly towards what he describes as "Gomorrah", the final stage or end point of the living, breathing political and cultural Slope on which we have already been and continue to be rapidly Slipping. Such "theories" or social "constructs", which inherently debase the inalienable value of newly existing unborn human lives, are now being tapped to ground the politically correct and absolutized concepts of "autonomy", perceived "social needs" and "convenience". The political and cultural consequences which he so carefully and at considerable length develops should give us immediate pause:

The systematic killing of unborn children in huge numbers is part of a general disregard for human life that has been growing for some time. Abortion by itself did not cause that disregard, but it certainly deepens and legitimates the nihilism that is spreading in our culture and finds killing for convenience acceptable. We are crossing lines, at first slowly and now with rapidity: killing unborn children for convenience; removing tissue from live fetuses; contemplating creating embryos for destruction in research; considering taking organs from living anencephalic babies; experimenting with assisted suicide; and contemplating euthanasia. Abortion has coarsened us. If it is permissible to kill the unborn human for convenience, it is surely permissible to kill those thought to be soon to die for the same reason. And it is inevitable that many who are not in danger of imminent death will be killed to relieve their families of burdens. Convenience is becoming the theme of our culture. Humans tend to be inconvenient at both ends of their lives.101(emphasis added)


Perhaps this is an appropriate point to at least raise the ticklish and often ignored question of both scientific and philosophical "expertise".102 It is clear from even the few arguments presented here that there are serious problems with both the scientific and philosophical inaccuracies pervading these arguments on "personhood".

The science used is often selective, cryptic and/or simply incorrect, and does not apply to or is irrelevant to the philosophical issue it is trying to ground. Some still insist that the "science" being used is correct -- although certainly to so "insist" does not make it so. We would all welcome those who support such "scientific" claims to prove them. When all of the human embryological, human genetic and other scientific texts -- as well as the most recent research and assurances by the most respected researchers -- state clearly and unequivocally that very different basic scientific facts are universally acknowledged which actually contradict the scientific "facts" used by many of the proponents of delayed personhood, let those proponents defend their scientific "facts" openly and publicly before an open body of their scientific peers.

What human embryologist, for example, would agree that ova and sperms are really the same as zygotes; that the zygote is not a human being or human embryo; that the early human embryo or fetus is just a "piece" of the mother's tissues; that human cells divide asynchronously and neatly into two, four, 8, etc.; that all of the cells at the two-cell stage are completely differentiated; that "totipotency" is somehow problematic, vague, or "indecisive"; that "molecular molecules" from the mother actually determine the very nature of the developing human embryo; that hydatidiform moles or teratomas derive from normal human embryos; that scientifically there is any such thing as a "pre-embryo", a "developmental individual" or an "ontological individual"; that none of the cells from the trophoblast layer ever find their way into the fetus or even the adult human being -- or that none of the cells from the embryoblast layer ever find their way into the placenta, etc.; that twinning never takes place after 14-days; that implantation takes place at two weeks; that the physical brain is parallel to the physical nervous system or primitive nerve network, or that either is fully integrated by the eighth week; or that full sentience or rational attributes are present anytime before birth (or beyond)?

What chemist would agree that the sharing of electrons when Na and Cl combine changes the very natures of these elements, or that the nucleus of a radioisotope is physically or chemically analogous to the nucleus of a living plant or animal cell?

Such basic scientific inaccuracies are academically difficult to explain.103 Why don't other scientists publicly or privately refute such scientific mis-information? Might they lose much needed research grants if they did? At what point does such scientific mis-information become unethical -- especially when it degrades and corrupts these very sciences, and is then applied and used to determine the moral status of certain human beings?

The philosophy that is often invoked is just as selective and problematic. Sometimes the "philosopher" apparently has had no background in the history of philosophy, and seems to be totally (or conveniently) oblivious to the theoretical problems inherent in any philosophical position with a mind/body split, or with rationalistic or empiricist philosophical presuppositions. Nor does there seem to be the least awareness that these philosophies are not really viable -- but interesting today mostly from an historical or propadeutic perspective, i.e., examples of how such systems historically have failed. Sometimes an historical philosopher is depicted with gross imprecision, or completely out of context -- making that historical philosopher "say" things he never would or could conclude to.

There is no way many "quotes" from Aristotle, Aquinas or Descartes can be sustained academically. And it is hardly a new academic insight that the Aristotle of the De Anima is and has been (for centuries) highly problematic and contradictory to his main-stream metaphysical doctrines on substance and anthropology.104 Nor did Aristotle or Thomas even mention "proto-matter", and both argued that "prime matter" doesn't even really exist. Neither would have defined "substance" as "mass-energy"; nor equated "quantity" with "mass". And Thomas would have always included esse in his definition of any "substance". Nor are the proper academic distinctions made among the several different kinds of Thomists (e.g., neo-platonic, aristotelean, suarezian, transcendental, maritainian, rahnerian, process, etc.,105many of whom read St. Thomas differently and conclude to different theories on these issues.

Descartes' philosophy was abandoned hundreds of years ago because of its multitudinous theoretical problems -- not only because of its mind/body split, belief in innate ideas and that there were only two substances in the entire universe (Mind and Extension), and neo-platonic epistemology -- but also because of the blatantly erroneous and absurd scientific theories to which it led (e.g., his theory of the "vortex").106 These basic philosophical are likewise difficult to explain.107 Again, let the "philosophers" in these "personhood" debates defend their philosophical positions with their mind/body splits, as well as their historical philosophical "depictions" and interpretations, openly and publicly before a body of philosophical scholars. Or would that be considered too "uncollegeal"? At what point does "collegiality" become unethical -- e.g., when it corrupts and degrades the history of philosophy, and is then also applied to determine the moral status of certain human beings?

This observation has serious implications for the assumed "professional" status of researchers, philosophers, ethicists and bioethicists -- issues which have received too little attention, especially in light of the current movement of the theories of these writers out of the "ivory towers" of academia into the domain of public policy. Scientific, philosophical, ethical or bioethical "experts" are being used more and more as "expert witnesses" -- for example, in the media, courtrooms, Congressional hearings, and federal panels -- to help to determine health care and medical research issues in public policy. It would seem that they should at least be held to the same standards of professional activity as are other "professionals" who have as significant an impact on the public welfare. Interestingly, these four "professions" are not even listed in the Codes of Professional Responsibility108 -- although physicians are. I do not consider myself an "expert" in any of these fields at all, and surely I am fallible as well. But given their impact on public policy, certainly there must be some bare minimum of standards in these fields below which one can not go without expecting to be held professionally accountable.

As "food for thought", consider the above-mentioned Codes. Among the criteria used as standards for "professionals" in that work are: accountability and responsibility; competence and qualifications; education, training and experience; law and legal requirements; licensing, certification, and accreditation; and other codes, bylaws, policies and technical standards -- to name but a few. A glance down the list of "professions" included under these standards of behavior reveals some interesting examples:

1. Accountability and responsibility (p. 479): These professions state specific "codes of professional conduct" or "codes of ethics": accountants, arbitrators, architects, bankers, business executives, clinical social workers, counselors, dental hygienists, dentists, engineers, financial planners, government lawyers, hospitals, insurance agents, journalists, lawyers, legal assistants, lobbyists, mediators, neutrals, nurses, personnel consultants, physicians, prosecutors, psychiatrists, psychologists, public administrators, real estate agents, social workers, and trial lawyers.

Note that researchers, philosophers, ethicists and bioethicists have no formal professional code of ethics, and no formal professional standards of behavior.

2. Competence and qualifications (pp. 485-486): These professions state specific requirements which must be met before practicing, including the mastery of a defined body of knowledge and the attainment of professional degrees which reflect similar requirements; many require testing on local, state or national levels: accountants, advertising agencies, arbitrators, bankers, business executives, clinical social workers, counselors, dental hygienists, dentists, direct marketers, engineers, financial planners, hospitals, insurance agents, journalists, law librarians, lawyers, legal assistants, mediators, neutrals, nurses, physicians, prosecutors, psychiatrists, psychologists, public administrators, real estate agents, social workers, and trial lawyers.

On the other hand, biological researchers are allowed to use radioisotopes without having a course in nuclear chemistry, or chemists are allowed to use infectious microbes without having a course in microbiology or sterile technique. Also, one finds metaphysicians teaching bioethics with no previous course work, ethicists teaching metaphysics with no previous course work, and bioethicists teaching metaphysics and ethics with no previous course work. Wouldn't it be odd to find a lawyer teaching organic chemistry with no previous course work in organic chemistry? As someone once aptly put it, "you can't teach what you don't know". And although philosophers, ethicists, and bioethicists must meet the idiosyncratic requirements of their degree institutions, there are no local, state or national testing requirements or standards to meet in order to assure the public of any common degree of competence or mastery of a similarly defined body of knowledge.

3. Education, training and experience (p. 492): These professions go beyond the above standards by requiring constant professional up-dating of information under formal, systematic conditions, as well as competence in specific training and a clear demonstration of effective experience: accountants, advertising agencies, arbitrators, architects, bankers, business executives, clinical social workers, counselors, dental hygienists, dentists, engineers, financial planners, hospitals, insurance agents, journalists, law librarians, lawyers, legal assistants, lobbyists, mediators, neutrals, nurses, personnel consultants, physicians, prosecutors, psychiatrists, psychologists, public administrators, real estate agents, social workers, and trial lawyers.

Note that researchers are not required to take courses in research ethics; nor do physicians or nurses necessarily know how to do basic or clinical research. Nor do philosophers, ethicists, or bioethicists have uniform requirements for course work, yet alone even agree on how to define the subject-matters of their disciplines. There are no requirements for updating their bodies of knowledge, there are variable degrees and levels of post-degree training -- if any -- and there are no determinable formal and global professional oversights or requirements for any experience.

Of particular interest is the fact that many public policy issues discussed here (and others) have been grounded on bioethics and its three basic principles of autonomy, justice and beneficence ("principlism").109 But if "principlism" is no longer acknowledged as a viable basis on which to ground even bioethics,110 then how can all of those local, national and international regulations, guidelines and documents -- which were explicitly grounded on "principlism" -- any longer be valid themselves?

4. Law and legal requirements (pp. 500-501): These professions go even further and require their members to practice their professions within certain local, state and federal legal requirements: accountants, advertising agencies, arbitrators, architects, bankers, business executives, clinical social workers, counselors, dental hygienists, dentists, direct marketers, engineers, financial planners, government lawyers, hospitals, insurance agents, journalists, law librarians, lawyers, legal assistants, lobbyists, mediators, nurses, personnel consultants, physicians, prosecutors, psychiatrists, psychologists, public administrators, real estate agents, social workers, and trial lawyers.

There are virtually no local, state or federal legal requirements restricting the practice of philosophers, ethicists or bioethicists.

5. Licensing, certification and accreditation (pp. 501-502): These professions require that their members obtain local, state or federal licensing, certification and/or accreditation before they are even allowed to practice: architects, clinical social workers, counselors, dental hygienists, dentists, engineers, financial planners, hospitals, insurance agents, lawyers, legal assistants, mediators, nurses, personnel consultants, physicians, prosecutors, psychiatrists, psychologists, real estate agents, and trial lawyers.

Although physicians and nurses are required to be licensed as care givers, they are not required to be licensed as clinical researchers; nor are bench scientists required to be licensed to do basic research. Clearly philosophers, ethicists and bioethicists are not required to be licensed or certified to practice on any local, state or federal level.

In these times of specialization, many "insist" that we must rely on the "professional expertise" of others. But if this and other studies on the arguments for "personhood" indicate anything, it is that one still must question the kind of "expertise" abounding today. If one prefers to propound a scientific/philosophical/ethical/bioethical theory that the world is made up of "quadrads" or "zeta particles", for example, and that a human being is defined in such terms, such a theory use to be academically entertained "indulgently". But today, when such theories are taught as fact to thousands of students, and further incorporated into local, state, national and international public policies and guidelines which effect the health, welfare and very lives of multi-millions of innocent human beings, then such theories, as well as those who espouse and promote them, ought to bear serious accountability to the public who eventually bears the brunt of such theoretical mis-information.

Given the scientific and philosophical problems inherent in the positions which argue for the various biological marker events of "personhood", can we really accept their various conclusions? Can we accept either the "science" that is used or the rationalistic or empiricist philosophical definitions of human beings or human persons which are incorporated into those arguments? Or is it even possible to reconcile the correct biological facts with a philosophical definition of a human being or a human person?

What I am leading to is a definition which does not split the human being from the human person, and which does not consist of only a part of the human beings of which we have experience. Can you really have a human person without simultaneously having a human being? And vice-versa, can you really have a human being without also simultaneously having a human person?

I would argue no -- you really can't split them -- except conceptually, as rationalistic or empiricist philosophers are wont to do. But if you do define a human person as only a part of the whole complex -- i.e., only in terms of matter, or sentience, or soul, or a part of the soul, or rational attributes -- then you will also logically have to argue not only for delayed hominization, but for the infanticide of even normal healthy infants or young adolescents, the substitution of the mentally ill in destructive experimental research, and the abuse and possible euthanizing of many sick human beings (especially the elderly) as well. And delayed hominization simply does not match up with the correct empirical facts.

Philosophically what has occurred is that a "part" of a whole has been turned into a whole thing itself (e.g., the "soul" alone, or the "body" alone are considered separate independent substances in themselves). And, of course, this leads to the chronic Platonic or Cartesian problems of a mind/soul, soul/body, or even a body/body split -- with all of the accompanying chorismos or "separation" problems latent in those philosophical position (such as no possibility of any interaction between the separated "body" and the "mind" or "soul").

However, if we look closely at the earlier Aristotelean-Thomistic ball-park definition of a human person I would submit that -- oddly enough -- it matches the most contemporary body of scientific facts that are available today. For example, at fertilization substantial change has taken place, resulting in an embryonic human zygote possessing 46 chromosomes, and a human nature or potency which contains all of the information needed to effect or cause specifically human accidental or embryological change or development. And this original information is not lost until the death of the adult human being. Biological phenomena, such as totipotency, "positional molecules" and even twinning are really normal phenomena which are suppose to happen, and are explained by the human genetic information in the original single-cell human zygote. Once the biological facts are correctly understood it is not difficult to define a human being.

From empirical observations we can then draw our objectively based philosophical concepts of personhood, and these philosophical concepts should surely reflect or match those biological facts as accurately as possible -- or else we are not philosophizing about the real world at all.

I have attempted to demonstrate, however briefly, that to define a "human being" or a "human person" in terms of only a part of the whole leads to counterintuitive and incomplete expressions of what we actually experience about human persons, as well as a miss-match with the correct empirical facts. The definition of a "human being" or a "human person" does not have to be relative -- as long as the correct science is employed, and our philosophical definitions actually match that reality. I leave it up to you to decide which of the proffered definitions make that match.