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Category: Truisms

Obvious truths. No, really.

The place of religion in democratic secular countries

There is a religion which oppresses women, which is enthusiastically adopted by marginalised groups, which hates democracy and which has declared the modern world to…


Notes on Novelty 8: Conclusion – Post evo-devo

Notes on Novelty series:
1. Introduction
2. Historical considerations – before and after evolution
3: The meaning of evolutionary novelty
4: Examples – the beetle’s horns and the turtle’s shell
5: Evolutionary radiations and individuation
6: Levels of description
7: Surprise!
8: Conclusion – Post evo-devo

With the growth of developmental genetics, it is possible to see beyond the view of homologies working at the level of whole organs. The mechanisms that define the ordinate axes of structures, the genetic circuits that pattern them, and the cell types with which organs are formed can be considered. The more that researchers look, the more they will find that the same tools have been used to build a great variety of structures long thought to have independent histories. Discerning what has been conserved and what is novel in the origins of organs and body plans will be possible only with more comparative data, experiments on non-model animals, and targeted fossil discoveries from crucial nodes in the tree of life. (Shubin et al. 2009: 822)

My conclusion is that we find novelty in a subjective sense, based upon what we think we should find in the data. Further knowledge of the underlying or overlaying mechanisms should reduce the surprisal of the trait appearing either in the paleontological record or in a distinct taxonomic group. Only when it doesn’t and in cases where it should, should we start to seek non-Darwinian mechanisms. Much of the debate over novelty in evolution has centred implicitly around what the researchers themselves find interesting, surprising or contrary to the conventional interpretations. Another factor lies in a topic I haven’t discussed here: what counts as “suitably dissimilar”, so a few words on this.

Similarity and its converse, dissimilarity, is often applied to the issues of novelty. Stephen Jay Gould attempted, for example, to apply it in the case of the Cambrian explosion (1990); some fossils’ bodyplans were too dissimilar (using the consistency index of cladistic analyses, C) to put them into existing taxonomic categories (“phyla”); subsequent work did precisely that (Briggs and Fortey 2005). Relying upon morphology – that is, description at a certain grain (indeed, the only grain available to palaeontologists most of the time; cytological data is rare and molecular data nonexistent) – Gould found some traits and overall phenotypes too weird to fit into our classifications. Briggs and Fortey showed over several decades of work summarised in their paper that they could be seen as instances of stem groups of our present clade-based phyla (that is, phyla that have been made monophyletic).

What is similarity in taxonomy? It is true that rarely does this get any kind of analytic or quantitative analysis, especially in palaeontology, but that doesn’t mean there is no analysis underlying it of which the authors are not conscious (or think it too obvious to state). The best analysis of the recognition of similarity in the literature is that of Amos Tversky, who argued that the similarity of one thing to another is the overlap of features minus the unique features to each object, out of a “feature set” (1978). This is now called “Tversky Similarity”:

Tversky Similarity  [TS]

What is crucial to understanding similarity like this, which was developed for a generic psychological account and not just for science, is that the choice of features to evaluate (which may be entirely unconscious, or a cultural convention, or even biologically imposed) determines what counts as similarity in each case. With a different feature set, different similarity indices might arise, and indeed the history of science has been one of finding the “right” feature set (for example, in the case of elements and the periodic table, Scerri 2008).

The alternative to using apparent similarity, especially at a given grain of description (the gross morphology of the organism) is to use homology. Instead of treating the relations between organisms and specimens as a matter of what they “look like”, identify homologs and organise your groupings on that basis – this is the reason for cladistics. Homologies, not similarities in the eyes of the beholders, set up a baseline for assessing how novel a trait may be, and if we can find the developmental, physiological, molecular and environmental reasons for the novelties thus uncovered, so much the better. All I am criticising is the idea that somehow, in ways we can’t even properly articulate, we need to “go beyond” or “extend” the Darwinian approach. In one sense of course we do; Darwin did not know everything. In this case, we do not; Darwin has been validated again and again regarding novelty.

I am not dismissing the idea that there can be an evolutionary explosion from some novelty or node in an evolutionary tree, although these are more often the result of subjective assessments (the Cambrian explosion has, for example, become less and less of an explosion and more and more of an evolutionary diversification of the ordinary kind, as paleontological evidence has come in). What I am dismissing is the notion that there is some objective sense in which evolutionary novelties are natural kinds. Radiations occur all the time – some clades are speciose and others are sparse. If there is a general principle why this occurs, it is not yet obvious. Maybe some kinds of developmental modularities do cause clades to be more radiative. Maybe, however, is not an explanation.

Science progresses best when it eliminates subjectivity from its categories; anthropomorphism has ever been the bugbear of good science (unless anthropoi are the objects of study, and even there we tend to project ourselves on our subjects, as any anthropologist can tell you). It has taken us over a century to begin to recognise that what Darwin started requires this in biology as in the other physical sciences. So I would like to leave the last word to somebody of a certain weight in evolutionary biology, and who seems to be on the right side of the debate on many issues, Sewall Wright:

“Creative” and “emergent” evolution

The present discussion has dealt with the problem of evolution as one depending wholly on mechanism and chance. In recent years, there has been some tendency to revert to more or less mystical conceptions revolving about such phrases as “emergent evolution” and “creative evolution.” The writer must confess to a certain sympathy with such viewpoints philosophically but feels that they can have no place in an attempt at scientific analysis of the problem. One may recognize that the only reality directly experienced is that of mind, including choice, that mechanism is merely a term for regular behavior, and that there can be no ultimate explanation in terms of mechanism—merely an analytic description. Such a description, however, is the essential task of science and because of these very considerations, objective and subjective terms cannot be used in the same description without danger of something like 100 percent duplication. Whatever incompleteness is involved in scientific analysis applies to the simplest problems of mechanics as well as to evolution. It is present in most aggravated form, perhaps, in the development and behavior of individual organisms, but even here there seems to be no necessary limit (short of quantum phenomena) to the extent to which mechanistic analysis may be carried. An organism appears to be a system, linked up in such a way, through chains of trigger mechanisms, that a high degree of freedom of behavior as a whole merely requires departures from regularity of behavior among the ultimate parts, of the order of infinitesimals raised to powers as high as the lengths of the above chains. This view implies considerable limitations in the synthetic phases of science, but in any case it seems to have reached the point of demonstration in the field of quantum physics that prediction can be expressed only in terms of probabilities, decreasing with the period of time. As to evolution, its entities, species and ecologic systems, are much less closely knit than individual organisms. One may conceive of the process as involving freedom, most readily traceable in the factor called here individual adaptability. This, however, is a subjective interpretation and can have no place in the objective scientific analysis of the problem. [Wright 1931: 159]


The principle of charity, qualia, and philosophy

I’ve hurt my back, so I aim to rant a little.

When I teach critical reasoning just about the first thing I teach is the principle of charity. It has many formulations:

This policy calls on us to fit our own propositions (or our own sentences) to the other person’s words and attitudes in such a way as to render their speech and other behavior intelligible. This necessarily requires us to see others as much like ourselves in point of overall coherence and correctness—that we see them as more or less rational creatures mentally inhabiting a world much like our own. [Donald Davidson]

In its simplest form, it holds that (other things being equal) one’s interpretation of another speaker’s words should minimize the ascription of false beliefs to that speaker. [The Oxford Companion to Philosophy]

This [P of C] says that if interpreting as reasoning a passage which is not obviously reasoning yields only bad arguments, assume it is not reasoning. (The rationale for this approach is that we are interested in finding out the truth about things rather than in scoring points off people.) [Alec Fisher]

There are many other quotations, for which I am indebted to Neil Thomason. However, the general point is that, when arguing with somebody, and they say something that seems on the face of it silly, try to reframe the statement so it makes the maximum amount of reasonable sense – that is, if the person’s statement can be reasonably interpreted in a coherent manner, do so.

We often interpret people as saying something that is truly silly in order to deprecate the arguments they make (this is called erecting a straw man, on the grounds that it is easy to knock a straw man down*). Consider what that implies about you: you do not use reason to find out try things, you use it to win arguments and reassure yourself. It isn’t knowledge that you seek but comfort and smugness.

Argument is supposed to give you a true conclusion if the premises are true and the argument is valid (technically, this is called a sound argument – but the term “sound” has, like so many other good terms, been hijacked by propagandists for rhetorical rather than rational purposes). This means that it is a way to work out what believing in true statements commits you to further believing, if you are a reasonable person. When you take the premises of observation that biological things vary more or less randomly in heritable ways, for example, it is a short but sound argument to the conclusion that, unless something intervenes to prevent it, all populations of living things are evolving. A rational person should believe that conclusion, because if the facts are true, the conclusion must be.

But if you try to leap onto missing premises or steps in the argument (an argument missing parts that are implied of assumed and which would be needed to make it truly sound or valid, is called an enthymeme, a term used by Aristotle, of course), just to score a point, you are not seeking truth, nor wanting to be rational.

What triggered this elementary introduction to reasoning is the way some (well meaning) commenters on this blog addressed my claim that there are no qualia. A quale, in philosophy of mind, is a feeling or experience, the “what it is to be like”, that cannot be reduced to a physical description. For example, Thomas Nagel’s famous paper “What it is like to be a bat” argues that we can know everything about the sensorium of bats, but not what it is like to be a bat with sonar. Likewise, Frank Jackson’s paper “Epiphenomenal Qualia” argues that a super scientist Mary in her room, which does not have any red light or colour, can know everything there is to know about light, vision and neurology associated with seeing red, and yet, when she is finally released and sees red for the first time, she experiences something she did not know.

This amounts to the claim that there is an ontological difference between the objective world, and the subjective world, a view that has deep roots, but is mostly associated with Kant and his heirs and successors. The term qualia (the plural of quale) indicates that we have experiential or phenomenological properties that are simply not reducible to factual statements (usually of physics, but you can take it in other ways, so long as the facts are objective).

For someone who thinks the world comprises one domain of being like me (I am an out and out physicalist), this presents a problem. David Chalmers dubbed this (inadvertently, I think) the Hard Problem (as opposed to the hard problems of building or simulating brains): how to account for consciousness in a physical universe. Qualia, phenomena, self-awareness, and so forth form a cluster of concepts that a monist/physicalist like me has to account for. They are assumed by many as truisms. Jackson and others give what I consider are question begging arguments for them, but at least they give arguments.

So, when I deny the existence of qualia and/or consciousness/the self, how should I be read? Assume I am not an idiot, just for argument’s sake. How might you read my claim? Well you might apply the Principle of Charity here and try to figure out what I am doing. You might ask “Where does Wilkins do a logical dance to get to this conclusion?” instead of saying “Wilkins is an idiot and a fool to deny what we all know to be true.” What we all know is in general terms a very good indicator to what is false.

You might think: “Wilkins must either have an argument that experience does not lead to the conclusion there are qualia or there is a self, or he must deny the premises that there are raw feels, or both”. And you would be right. I do both. On the one hand I assert that contrary to the widely held view, there is only a purely verbal existence of raw experience. In short, we have these words “feeling”, “experience” and “awareness”, and so we just sort of assume there are feelings, experiences and awareness in these special ways. Instead, I think that we can use the words without committing ourselves to the folk ontology† as we do things that “feel”, “experience” and “aware” refer to. These are, of course, objective processes, even if we can’t directly inspect them without killing the subject.

On the other hand I deny that having an experience is itself a reason to believe in qualia/consciousness. Instead I think we are all P-zombies anyway. Remember, a P-Zombie is just like you and me in every physical and behavioural respect, only without qualia or consciousness. You cannot tell, nor can they, that they lack these. They report pain and every other experience under the right circumstances.

So qualia are not objective, right enough. Now suppose that it happens that in this world, we are all P-zombies, but do not know it. Instead we all only think we have qualia (why? because language often leads us to think things that aren’t true, as Wittgenstein often said). We cannot tell that we do not. This is a thought experiment, but it has a sting: I am not merely giving it as a hypothetical, I am saying that we have no reason not to think it is the case.

Everybody has experiences, and because everybody is in a unique situation, both bodily, location wise, and circumstances, every experience is unique to the timeline of that individual. So I must assert that experiences are unique. There is only a “what it is like to be Wilkins” available to Wilkins, except in terms of general classes of experience (suffering pain from pulled lower backs comes immediate to mind right now), which are quite addressable as objective phenomena.

But this doesn’t license the ontological claim of the separate reality of the subjective. To be a subject in my view of the world is just to have a perspective, as I argued before. It is to be this thing, here, now. I’m not denying that you have these experiences, only that they mean there is a subjective world separate from and irreducible to the physical objective measurable world.

To return for a second to the Principle of Charity, one commentator exhibited a common response, often seen when scientists criticise philosophy: attacking the fact that there is a term of art in philosophy that means what the non-philosopher thinks is contrary to intuition or “common knowledge”. Qualia was defined as a term of philosophy to mean irreducible experience. By denying that experience is irreducible I must, perforce, deny that qualia exist. I could redefine it to mean “experience” but we already have a word for that: “experience”.

Philosophers often seem to the outside as if they are quibbling over meanings and splitting hairs. Meanings, of course, matter, and calling something “mere semantics” to a linguist will get you a well deserved rap on the knuckles, but philosophers do a fair bit more than that. They also reconstruct the arguments necessary to make usages of words rational, or try to show that the arguments fail to do this. We do it in the name of truth, even if a certain number just enjoy playing the game the way a tennis star plays tennis, by stretching the rules as far as they will go for competitive advantage.

And finally, here’s a thing: scientists, skeptics, religious believers, politicians, economists and every other group of people also do precisely this, although they usually do it poorly. Consider how bad reasoning led to the Iraq invasion. Imagine how much better the world would be, if the intelligence analysts to a person had used good reasoning skills. Deprecate philosophy at your peril, oh smug ones!

Okay, the pain killers have kicked in and my back is no longer driving my expression of bile and bitterness, so I will sign off for now. As Craig Ferguson says, I look forward to your letters.