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9th Postgraduate Course for Training in Reproductive Medicine and Reproductive Biology

Biology and ethics: the paradoxes of the natural

Alex Mauron
Associate professor of bioethics


This presentation has a two-fold purpose. Firstly it analyses several ways' in which biology and ethical reflection interact in contemporary bioethical discourse. These interactions are multiple because, on the one hand, a great deal of bioethics is about biology. Bioethicists discuss and evaluate in ethical terms various biological advances such as gene therapy, genetic screening or embryo experimentation. But on the other hand, biology, or rather some aspects of it, could conceivably be about ethics. Ethics is concerned about certain aspects of human behaviour, such as co-operation, competition, altruism reciprocity; and biology has something to say to these matters. An other way of putting it is that ethics and biology have a common, and conceivably overlapping, interest in human nature. This leads to the second aim of this paper: to give an overview of the way concepts of nature and the natural operate in various kinds of ethical evaluations. This will be a very modest overview rather than an in-depth philosophical analysis, given the great diversity of ethical, concerns and arguments in which such concepts play a role.

At this point, it is already apparent that there are two sides to the relationship of biology and ethics, one quite essential but basically limited and in some sense trivial, the other much less obvious, perhaps less trivial and certainly much more controversial. As I alluded to before, the first relationship originates from the nature of bioethics itself. For if we define bioethics as a reflective effort to clarify the ethical implications of biomedical progress, the biologist has an obvious role in it. Biologists participate with many other scientists and physicians to the production of new biomedical knowledge, which translates more or less rapidly into novel technological possibilities. Among many other things, these entail new ways of "manipulating genes", of deciphering genetic information, thus generating predictive information about human beings and opening new medical options; they give rise to techniques that make possible the production of materials and organisms not present as such in nature; they open up new ways of intervening in human reproduction. These new opportunities for action create new human responsibilities and bioethical reflection is called upon to sort these out. In other words, whether we think of the prospects for gene therapy, or perhaps more importantly of the new genetic diagnostics and what is increasingly called predictive medicine; or more importantly still, the fantastic impulse that molecular genetics has given to virtually every branch of medical science; in all these developments, biology has been central as the originator of the subject-matter of bioethical reflection.

Therefore, in this first perspective, the biologist has a central, yet very limited role: that of a "problem-maker". Biologists are basically seen as creating ethical quandaries for others to solve. This is reflected in the style of "polite" interdisciplinary that prevails in some -mercifully not all- bioethical symposia. The scientist on duty is kindly requested to explain the subject-matter of, say, gene technology or in-vitro fertilisation or whatever is the topic of the day. Then, there is a change of scene: philosophers and theologians explain to the rest of us what one must think in moral terms about these new developments. At this point, if a scientist intervenes not simply to make a factual point but to offer an ethical argument, one sometimes senses a slight irritation, as if the scientist was reaching beyond his expertise towards ethical questions that aren't his business. There is an assumption that scientists are there to provide the bare facts and that it is then for ethicists and moralists to conduct the moral analysis and come up with the normative answers.

But this view is far too restrictive and neglects the fact that biology and ethics interact at a deeper, more conceptual level, if only because the question of human nature is basic to both.

To make a very long story very short, biology tries to explore human nature by asking two kinds of basic questions that R. Alexander, following E. Mayr, calls "how?" questions and "how come ?" questions respectively. "How?" questions are about proximate causes of living phenomena. These are the questions investigated by physiology, biochemistry, genetics, ecology, you name it. They are synonymous with the question "how does it function?", where "it" stands for a macromolecule, a metabolite pathway, a cell, an organ, the behavioural repertoire of an organism, a population, an ecosystem. Virtually all biomedical science belongs to this category. But "how?" questions are not the only ones addressed by biology. For instance, if I ask the question "how come the human hand has five fingers?" this is an altogether different sort of question. At first blush, it looks like a question of developmental biology but this not strictly true: developmental biology will tell us for instance what cellular mechanisms shape the primitive limbs and how programmed cell death will turn a palmed hand into a five-fingered hand, but it will not really explain why there are five rather than four or ten fingers. To answer this, we must turn to comparative anatomy and start investigating the number of digits on the upper limb of mammals, vertebrates, and so on. In other words, the "how come" question is an evolutionary one. Evolutionary considerations are essential to an understanding of human nature and since ethical attitudes are linked in some way to the specifics of human nature, evolutionary biology is relevant to these as well.

This is not to say that the connection between ethics and human nature is a straight and simple one. Quite to the contrary, the question of ethical naturalism is loaded with historical baggage, most of which consists of ways to make the connection that have not withstood the test of critical inquiry. A traditional approach to moral problems has been to consider whether a particular course of action is consonant with human nature and essentially human purpose and flourishing. The underlying assumption is that human life has a definite purpose, either set by divine command or somehow inscribed in nature itself. There is another sense in which nature in general, or "the natural", plays a role in moral language, namely the widespread intuition that "the natural" is closely connected to "the good". This is perhaps not prominent in philosophically sophisticated circles but is nevertheless an overpowering intuition that operates in many practical judgements in bioethics.

In summary, the themes of nature and of the natural provide an important area of conceptual dialogue between biology and ethics and this is explored here by briefly surveying three questions,

  1. What is the standing of appeals to "the natural" in ethical discussions, or what should it be?
  2. Is there a biology of morality, or should there be one ?
  3. Are there "natural" borders to the moral community ? Another question closely to this last one would be: where does the border between biological description and ethical evaluation run ? In many situations they are difficult to tell apart (one thinks of the question of animal rights, or of the ethical standing of the human embryo).

1. The natural as an ethical criterion.

The standing of naturalistic criteria in an ethical context immediately raises the well-known problem of the Naturalistic Fallacy. This term covers a wide range of arguments that should in principle be analysed separately. For instance, Hume's famous passage in the Treatise of Human Nature where he posits a basic distinction between "is" and "ought", between the descriptive and the normative does not make the same point as G.E. Moore's Principia Ethica, from where the term "Naturalistic Fallacy" originates. This is not the place to even begin to survey the intricate philosophical issues connected to the Naturalistic Fallacy and ethical naturalism. The point here is merely to suggest that there are difficulties in both extreme stances in the debate, vz. naive naturalism on one hand, extreme anti-naturalism on the other. Naive naturalism is what was rightly denounced by Hume when he points to the unanalysed and unsubstantiated deduction from "is" to "ought", from the descriptive to the prescriptive. It is perhaps easy to see this as a mistake in the abstract, but it is far more difficult to avoid the trap when discussing some particular concrete problem and examples of illegitimate naturalism are easily found in many bioethical discussions, as we shall see further. Extreme anti-naturalism is exemplified by G.E.Moore and other early 20th-century analytical philosophers, who were opposing the utilitarianism of J. Stuart Mill. Moore thought that utilitarianism was fundamentally flawed in trying to identify moral properties with natural properties. But he also opposed Hume's subjectivism. In fact, he believed that "good" and "bad" are objective, albeit non-natural properties and that just as we have our senses and our reason to perceive natural properties, we have a special intuitive modality of knowledge that lets us apprehend the moral properties of actions and behaviours. However, intuitionism is not a very appealing moral position if only because it reduces moral disagreements to a clash of incommensurable intuitions. The underlying difficulty is the very idea of a property that is objective, yet non-natural. Assuming that we do have a kid of built-in "moral module", a special nucleus ethicus in our brain that allows us to perceive and process moral properties, then calling this entity (and the moral properties that are its substrate) non-natural is simply a way of putting it in a black box to hide it from investigation. There doesn't seem to be a principled reason for that move.

So much for extreme anti-naturalism. Its problems do not absolve naturalism from its own a difficulties, however the idea that all variants of ethical naturalism are necessarily naive and misguided is an idea that is not persuasive. For instance, utilitarianism is clearly naturalistic since it interprets "the good" in terms of "pleasure" or individual preferences (which presumably are natural properties). Now, there may be many problems with utilitarianism but it cannot be dismissed out of hand simply because it is naturalistic, In a way, its being naturalistic makes utilitarianism arguable, because it can be argued for and against to the extent that its basic assumptions (identify the good with this or that natural property) are open to scrutiny because they reach to a common world of empirical experience. However, what is not sustainable is the common form of simplistic naturalism that simply identifies the good with the property of being natural This form of again removes ethical debate from the sphere of the rational.

Curiously the variant of naturalism that simply conflates the good with the natural is intuitionistic just like Moore's extreme anti-naturalistic stance. The reason is that in this perspective, only unanalysed intuition can tell us what is natural and what not. Clearly, "natural" cannot simply mean "in accordance with the laws of nature" because if that were the case, miracles would be the only unnatural, i.e. immoral, actions. God would be the Lone Cosmic Bad Guy. The naturalistic criterion, if it is not to be tautological, must be more discriminating and cut across the fabric of "all things possible" to use Bacon's expression. There must be actions, events or processes that are possible, yet unnatural. But then, the natural must point beyond itself towards some identifiable property, and so we are back to square one: what counts as natural ?

One idea that has pervaded many discussions of gene technology is the somewhat concept of "natural" as opposed to "artificial". For instance, regulation of DNA-based technologies or the release of genetically-modified organisms has usually been faced with the following two options:

  • regulate according to intrinsic risk;
  • regulate according to genetic history, i.e. the presence of a step of "artificial" recombination in the genealogy of the product or organism to be regulated.

This second option is buttressed by very strong intuitions, in spite of its obvious weaknesses. Throughout the history of the recombinant DNA debate, and even today, one observes that the "natural" is given a premium over the "artificial", quite apart from the identifiable risks that attach to one or the other. This is a very interesting phenomenon that has been studied by the American political scientist Aaron Wildavsky. His basic point is that Nature is to a large extent a social construct that social groups create in order to articulate various views about the good life. To a large extent, the conflicts around novel technologies are not objective in the sense of pitting rational arguments one against the other. They are also clashes of world-views, which are really nature-views. Wildavsky has tried to categorise them as four different concepts of nature to which he connects four ways of life.

"Cornucopian" Nature

The abundance and resilience of nature never cease to surprise us.
The individualist human ingenuity always finds a way to solve the problem.

Fragile Nature

The natural order is vulnerable. Even a small transgression can lead to catastrophic effects.
The egalitarian nature is exploited, oppressed.

Moderately tolerant Nature

Within margins, nature tolerates certain mistakes, Is causal properties are transparent.
The "hierarchist" experts know best, we need them, to sort things out.

Capricious Nature

Nature is essentially random. Its causal structure is impenetrable.
The fatalist there is nothing we can do. Life is a lottery.

Any one following debates on genetic technology, especially in a political forum, will easily recognise these views and the corresponding characters. It is clear that none of this nature-views is 100 percent right or wrong. Each in fact encapsulates important insights.

Nevertheless, being holistic world-views rather than just collections of individual ideas, they are incompatible and closed to each other. In the words of Wildavsky, each view of nature "recommends itself as self-evidently true to the people whose way of life renders them partial to that particular representation of reality". He goes on to quote another social scientist, sociologist David Bloor:

"Men use their ideas about Nature and Divinity to legitimate their institutions. It is put around that deviation is unnatural, displeasing to the gods, unhealthy, expensive, and time-consuming. These instinctive ruses map nature onto society. Nature becomes a code for talking about society, a language in which justifications and challenges can be expressed. it is a medium of social interaction ... Classificatory anomalies ... take on a moral significance. By these hidden routes they acquire the connotations of irregular social behaviour, which makes a response to them all the more urgent. One response is to- "taboo" the anomaly which violates the classification, declaring it an abomination and seeing it as a symbol of threat and disorder."

The relevance of this analysis for gene technology is obvious. Gene technology transcends, i.e. "violates", species borders and is therefore ideally suited to be subjected to these kind of taxonomic taboos.

2. A biology of morality ?

There is another area in which nature-based arguments are popular: conventional sexual morality. In that context, certain sexual practices (such as sex without procreation, or homosexuality) are condemned as being "against nature". Outside of specific conservative moral traditions, such arguments are rarely considered convincing nowadays, but the reason why they fail is itself an interesting topic for biologically-inspired philosophical reflection. These arguments fail even if one discounts the Naturalistic Fallacy. The reason is always the same. It is never clear what really counts as "natural". One could initially try to define it as that which is usually the case in the "natural state of man" (however defined, and possibly including non-human primates). But then all the supposedly damnable sexual practices turn out to be natural. We are back to the same square one.

Clearly, if any form of natural moral law is to provide normative guidance, it must be discriminating among different possible and existing behaviours and this brings me to my second question, namely whether there is some sort of biology of morality. We could conceivably try to find this selection element in some deeper level of biological normativity, by invoking some general biological law that has normative force even if it is broken occasionally. However, from the biological point of view, there is only one truly general biological law: the law of evolution by divergence from common ancestry and natural selection. But it is hard to see why "deviant" sexual practices would be evolutionarily disadvantageous. In fact, some sociobiologists have made a case for the biological usefulness of homosexuality (Weinrich), claiming that the homosexual uncle's parental investment in his sibling's progeny ultimately helps to propagate his own genes. In any event, even if homosexuality or any other behaviour was proven to be disadvantageous from an evolutionary point of view, that finding would be morally relevant only if we granted the highly dubious premise that we ought to follow the dictates of evolution. The weakness of this social Darwinist premise is apparent if we see that it is itself a moral thesis among others, that it is open to dispute as such and unable therefore to lift us up from the morass of moral controversy onto the safer grounds of factual disagreement. The law of evolution is no law at all, from the moral point of view. Back to square one again. What about a third possibility, namely to identify "the natural" with the ordinary dispositional properties of human individuals, such as for instance their genetic propensities (in a broad sense) ? But then, an even better case can be made for the naturalness of homosexuality, for example, if we grant the controversial conclusions of Hamer and Le Vay. And yet again, the moral relevance of the naturality argument itself can be questioned. In conclusion, it is hard to make much of naturality-based arguments in morals, which are often (but by no means always) failed attempts to translate religious moral precepts in a secular language thought to be more widely acceptable.

Generally speaking, one should nor expect biological considerations to lend much support to conventional morality. Such arguments can in fact lead to deeply paradoxical conclusions. For instance, let us consider the prohibition of incest. Just because incest is widely condemned in most human cultures, does it mean that this prohibition has a biological basis ? Firstly we should consider the fact' well known to anthropologists, that the limits and extent of the incest taboo does not coincide with consanguinity. The prohibition touches non-related individuals such as the second spouse of one's father, where avoidance of the genetic risks associated with consanguineous matings is not a factor. But the paradox runs deeper if we consider incest avoidance in a modern society. If the biological "purpose" of incest avoidance (i.e. the prevention of recessive genetic disease in the offspring) represents at the same time its moral justification, then consider the perplexity of the following couple : they are unrelated, to the best of their knowledge. They chance to discover by genetic testing that they are both carriers for thalassaemia major. If biology is the moral basis for incest prohibition, this couple is incestuous and should feel as guilty having sex as a parent-child incestuous pair, a conclusion which is patently ludicrous.

However, bringing in evolutionary considerations suggests another, more interesting, way in which biology and ethics interact. Charles Darwin was quite clear about his belief that natural

selection had operated in the emergence of homo sapiens just as for any other species, and that human behaviour displays adaptive features in the same way as morphology or physiology do. In The Descent of Man, Darwin advances the idea that the human moral sense differs in degree but not in kind from the instincts and behavioural propensities of animals. On that basis, he sketches out an interesting ethical theory, which has both utilitarian and Humean aspects. Nearer to us, social scientists using biological concepts have suggested that Evolutionary considerations can explain at least some dimensions of what we could call, in Humean language, the "moral sense". The phenomenon of kin selection shows that individuals can behave altruistically towards their kin for reasons that are rooted in Darwinian selection : selfless co-operation within ones kinship helps an individual to pass along a genetic endowment that is partly its own (Hamilton). Furthermore, reciprocal altruism can be biologically beneficial to unrelated individuals (Trivers). Some go so far as to postulate that there is a sociobiological basis for the Golden Rule and the Categorical Imperative (Ruse). Without being so overenthusiastic, one must conclude that a great deal of moral behaviour and of the ordinary moral beliefs may well have an ultimate basis in the evolutionary processes that attended to the biological history of mankind.

Does that make ethics a chapter of biology ? Regrettably perhaps, the answer must be no. The problem of ethical justification remains, whatever we discover about this Darwinian, rather than nietzschean, "genealogy of morals". In fact, a latter-day David Hume would be quick to point out that there is nothing inherently rational in our moral passions because their is nothing inherently rational in our evolutionary history. Evolution is contingent, not necessary. Furthermore, why should that which has evolved be thereby validated in a morally-relevant sense ? To believe so would make one slip into the simplistic pop-sociobiology recently exemplified by an Anglican bishop who claimed that polygamy is "in the genes" and therefore we should not be too harsh on philanderers.

Another, more pragmatic, way of showing the difficulties that a simplistic evolutionary ethics has with the problem of justification is to evaluate its consequence in today’s world that is beset by demographic problems. Taken literally such an ethic would have to view individual reproductive success as the ultimate value, since that is the ultimate touchstone of evolution. For evolution, more is better. In a purely Darwinian world, there is nothing repugnant to Parfit's famous "repugnant conclusion": more people add to the aggregate "happiness of the world" even if their quality of life is marginal. We must remember that from an evolutionary point of view, reproductive success is relative, not absolute. What counts is not absolute numbers, it is to have more offspring than the other individuals and populate an ecological niche successfully. If we consider the interests of humankind today, it is clear that the driving force of evolution is working at cross-purposes with its aspirations towards a better quality of life. As a result, a simplistic evolutionary ethic will be inadequate in its consideration of quality-of-life issues. Ironically perhaps, it would find itself in the same company as today's conservative, vitalistic moral traditions that deny the population problem flat out and brand "contraceptive mentality" as an evil. Both ethics are similarly maladaptive and fail to provide useful guidance to a world that must discharge its responsibilities to future generations in terms of quality of life rather than quantity. Today, contraceptive mentality should count among the cardinal virtues, contrary to what the Pope and Herbert Spencer would tell us.

All this does not mean that biology has nothing to contribute to the foundations of ethics or that an evolutionary ethics is a hopeless project: quite the contrary is true. But the Naturalistic Fallacy sets an ultimate limit to literal translations of biological data into ethical norms, as acknowledged by some of the most articulate defenders of a biological outlook on ethics (Alexander). In the words of the latter: "The value of an evolutionary approach to human sociality is thus not to determine the limits of our actions so that we can abide by them. Rather, it is to examine our life strategies so that we can change them when we wish, as a result of understanding them".

These considerations suggest a way in which a biological perspective may be useful in ethics even if -especially if- we do not consider biological nature to be normative in itself. Such a perspective provides useful background data for moral reform. It may tell us what evolutionary forces work for our purposes and which ones work against. This is useful to know even if we think that morality should be working against the "cosmic process" of evolution, as Thomas Huxley believed.

3. The "natural" borders of the moral community.

Much of the moral life concerns reciprocal relations between moral agents that are defined as equals. Classically, the principle of equality regulates the relationships between human persons. These can be seen as defining a moral community. However, current bioethical debates show that the borders of the moral community are fuzzy. For one, we do acknowledge moral duties towards non-human entities such as animals, for instance. We also accept that protecting plants, ecosystems, cultural goods are important norms, that may be considered prudential but have also moral overtones. Of course, that doesn’t mean that the moral community should include animals and plants, ecosystems, the Gutenberg Bible and the Duomo di Monreale. In fact, the classical solution is to consider moral obligations involving non-human entities as obligations regarding these entities not towards them. In other words, these obligations do not necessarily create correlative rights vested in animals, plants etc. However the utilitarian tradition from Jeremy Bentham to Peter Singer does propose an "expansion of the circle", a widening of the moral community to include all sentient beings. What is interesting in this move as regards our topic is that one natural criterion is replaced by another, i.e. the taxonomic criterion of belonging to one species is replaced by the criterion of sentience, thought to be less arbitrary.

Another aspect of the same problem is that we recognise moral obligations towards entities that are unquestionably human but not self-evidently persons. This is particularly the case of the various stages of human prenatal life and constitutes the central issue in the moral quandaries concerning abortion and contraception, as well of many end-of-life questions. Yet the problem itself is deeply paradoxical. On one hand, it seems obligatory to define some descriptive -and therefore implicitly or explicitly biological- feature that is necessary and sufficient to qualify for membership in the moral community. But on the other hand, most properties that have been proposed lead in one way or another to counter-intuitive moral claims, or can be shown to be incoherent, or commit the Naturalistic Fallacy. The paradox is especially striking as regards the status of the human embryo because there is a clear-cut material continuity between entities that nobody regards as persons (oocytes and sperm) and entities that are just as clearly persons (i.e. persons in the "ordinary" sense). So where does the switch to personhood occur ?

Many solutions have been offered in the bioethics debate and none of them is free of problems. I will comment briefly on one of them that asserts that the embryo is a member of the moral community ever since fertilisation, i.e. that the embryo is a person in a morally-relevant sense. This is of course a socially and politically important opinion. In fact, some of its proponents regard it not only as true but also as self-evident and claim that whoever denies it must have a vested interest in promoting abortion and other "immoral" behaviours towards prenatal life. They also sometimes claim that their position is a clear-cut consequence of the findings of modern biology: after all, doesn't science assert that ever since fertilisation a new genome is formed that is distinct from the genomes of both parents and thus marks the origin of a new individual ? Here we have an example of scientific knowledge being instrumentalized and pressed into service to support a particular moral position. It is therefore important to see why things are much more complicated than the defenders of the personhood-at-fertilisation thesis allow.

Firstly, there is often a confusion between the notion of a person as a normative concept, essentially synonymous with the bearer of human rights, and the concept of an individual, a purely descriptive concept that can be interpreted in several ways. Natural science doesn't speak directly to the concept of person since that notion belongs to metaphysical and ethical discourse. Science does have something to say about individuality however, as will shall see. Certainly, it would be unfair to ascribe this confusion between personhood and individuality to all defenders of an unconditional right to life of the human embryo. Many theologians for instance quite accept the difference between individual and person. However, they believe that once you have established a claim to individuality for the embryo, you also have a presumptive case for personhood. At this point, the next move is to invoke the so-called tutiorist argument and to claim that definite proof is not needed : presumption is enough. In other words the claim of the tutiorist is that if the embryo is a presumptive person, society should protect its presumptive right to life even if there is some uncertainty and controversy in the matter.

This line of argument is understandable coming as it does from a philosophical tradition that defines a person as "an individual substance of a rational nature" (Boethius). If one accepts that definition, one may well feel that by asserting that X is an individual substance, one has already met the requirements of the definition half-way. But these kinds of arguments are basically unsound. Even if it can be said that an embryo is an individual from a biological point of view, this has very little to do with the classical notion of an "individual substance", a notion that belongs to a pre-scientific ontological scheme. The biologically-informed concept of individuality is operational and relative. For one thing there is no single concept of individuality that can be applied consistently across the living world, which is not surprising considering that individuality in multicellular organisms is an evolved, not an a priori, property. But even if we restrict ourselves to homo sapiens, what do we really mean when we say "the embryo is an individual" ? Nowadays, everybody seems to realise more or less that this has something to do with genetics but the connection is far more complex than commonly believed. Genetic individuality in the etymological sense of being divisum ab alio, of being distinctive and separate in genetic terms is neither necessary nor sufficient to establish numerical identity. In fact if genetic distinctiveness by interposition of genetic change was the only defining property of an individual, we would have to say that gametes -sperm and oocytes- are individuals as well. But contrary to the well-known Monty Python sketch, no moral tradition known to me asserts that "every sperm is sacred". We may then turn to what might be called a genomic concept of individuality: a new individual is said to arise at fertilisation but not at meiosis i.e. when a new diploid genome is formed. But this is basically just a definition, not in any sense an empirical finding about the nature of individuality. Furthermore, it is a rather odd definition since it does not cohere with the notion of numerical identity, as is shown by the existence of monozygotic twins. If a zygote splits to give rise to two twins, the two resulting persons are obviously non-identical. Therefore the zygote from which they originate cannot be numerically identical to both twins simultaneously. This is a matter of elementary logic, not even of biology. Yet it illustrates a biological point, namely that genomic individuality does not map in one-to-one correspondence with the concepts of individual and of person in ordinary discourse, because it is not stably conserved in early embryonic development. One cannot use genomic individuality as a modern substitute of individualis substantia. As a result, the tactic of taking the moral intuitions that attach to the ordinary concept of person and pumping them backwards to ever earlier stages of prenatal development is bound to fail.

This - and it will be my conclusion- says something about the difficulty making sound naturalistic arguments in ethics. I am not claiming that it is impossible, only that it is beset with traps. For one thing, it is necessary to be conversant with the epistemological structure of an empirical science such as biology. Not every assertoric sentence of biological discourse ("the embryo is an individual") is a report of an empirical finding. To believe so would imply a naively positivistic view of science as basically a pile of facts. There are other kinds of statements in science, such as definitions ("the 'embryo is defined as an individual"). Definitions have a different standing. Nevertheless to overcome these difficulties is a worthwhile endeavour for philosophically-inclined biologists and naturalistically-inclined philosophers. It may even be a necessary endeavour if the connection between the descriptive and the prescriptive is to be understood, as opposed to be either taken for granted or put in a black box called "Naturalistic Fallacy".