Preamble: I am going to republish (and where appropriate, update, some of my old more substantial pieces on the blog. This is the first.
This three-part series is a talk I gave a while back to some ecologists and molecular biologists. It is a brief overview of the aims and relationship between science and philosophy of science, with a special reference to the classification wars in systematics, and the interface of science and the broader community. I will present my own overview of the elements of science – as a dynamic evolving entity of knowledge gathering rather than as a timeless methodology or as a purely social movement.
It isn’t often that an ornithologist gets to talk to birds. It’s even less frequent that they have an interest in the ornithologist’s point of view. Most rare of all is that the birds can talk back. And as for them being interested… But this is the position I find myself in today, so I hope you’ll forgive my nervousness.
What I’m going to do is to give an overview of the philosophy of science – necessarily a personal view of it – before I cover some of the topics we usually discuss. Then, I will describe a view of science as a dynamic historical evolutionary process which I think is the most realistic and fruitful view. Towards the end, I’ll suggest some ways in which philosophy, unlike ornithology, can assist its subjects, and then we’ll look at a couple of issues to see how this plays out.
One might ask what value philosophy has for science, and I’ve heard a number of scientists suggest, more or less tactfully, that philosophy is less than useful in the real world. In fact, some of my scientist friends are very untactful in making that suggestion.
But this is undercut to a degree by the fact that scientists themselves do philosophy. I once heard a theologian say that all Christians do theology, and the difference is whether they do it well or badly. Likewise, everybody does philosophy. The question is whether they do it well, and reduce confusion in their thinking, or do it badly, and increase it. Scientists like Stephen Hawking, Ernst Mayr, Stephen Jay Gould, Richard Dawkins, and so forth, all advance philosophical agendas and arguments in the course of interpreting their science. It’s only fair that philosophers get a look-in from time to time to see whether they do it well or not.
So we should start with the question of what the philosophy of science is, and how it came to be a distinct discipline, distinct, but not separate, from general philosophy.
What is philosophy of science?
Traditionally, philosophy has always dealt with the logic and methods of science, as far back as the scientific revolution and John Locke, who famously said that philosophy cleared the undergrowth to permit science to grow. In the wake of the massive developments in science in the nineteenth century, philosophy started to separate into distinct disciplines, one of which was scientific philosophy, which became, around the middle of the last century or a bit earlier, philosophy of science.
At first, the philosophy of science focussed on physics and astronomy as the “standard” notion of what a science was, and so much discussion centred on what made a physical theory a good one. A lot of it relied upon there being “laws” in scientific explanation. Once the focus shifted, around the 1960s with the rise of molecular genetics, to biology, it was immediately claimed that biology, lacking laws, was either not a science or some other kind of science. Of course, then people also began to argue that biology does have laws, and so an ongoing debate began.
Some of this debate dealt with an issue in the philosophy of science generally with went by the title of “reductionism”. This is the question of when one theory or domain of science can be explained by reducing it to another theory or domain. Hence, in biology, Mendelian genetics was said to be reducible to molecular genetics, in that all the entities and processes of Mendelian or population genetics could be accounted for by the entities of molecular genetics. Those who opposed this called themselves “holists”, based on the ideas of several prior philosophers and popular writers like Arthur Koestler. It has been said by G. C. Williams, the evolutionary biologist, that what distinguishes holists from reductionists in biology is the size of their glassware.
Recently philosophy of science has differentiated into several subdisciplines – there’s the philosophy of mathematics, which in recent years has dealt with, among other things, the use of Bayesian reasoning to make inferences and test hypotheses. In particular, the field known as “confirmation theory” has developed on from the old Popperian view that all science does is falsify hypotheses, not confirm or generate them in any systematic manner.
Then there’s the old standby, philosophy of physics, which these days can include time-travel and cosmology. But now, and most relevant to this audience, is the philosophy of biology. Philosophy of Biology started up in the period between 1959, when Morton Beckner published his The biological way of thought, and 1974, when David Hull published his Philosophy of Biological Science. It has generally covered mostly the philosophical implications of genetics and evolution. Genetics raises issues of what causes organisms, and in particular humans, to be what they are. It has affected discussions of race, ethics, medical research and public policy, because it deals with the animal that everybody knows, us. Evolution raises a range of different issues, ranging from whether we are selfishly determined to serve our own interests or those of our genes, to whether life is predetermined in how it unfolds. And it is interesting in its own right, of course.
But evolution and genetics are not the whole of biology. More recently a field of the philosophy of ecology has developed, and we also look at the area that is closest to my heart, that of biological classification, which is squarely in the old philosophical issues of logic.
So let’s look at what the issues are in the philosophy of science.
First and higher order questions about science
Philosophy of science asks questions about science. Some of these are zeroth order questions like, “Is hypothesis X a good one?”, which any scientists can and should ask. But we also ask first order questions like, “What makes hypothesis X a better hypothesis than hypothesis Y?” This leads philosophers to either say that the matter is without an answer, which is rare (nearly all philosophers of science agree that science does find things out and explain them better than before), or to offer an account of comparing and choosing between competing hypotheses. These are first order questions. This then raises second and higher order questions that abstract away from scientific practices and ideas – why should a given account of why science succeeds be accepted over another? and so forth.
First order questions can also include analyses of some of the core concepts that are used in science – like “species” or “cause” or “correlation” or “gene”. Sometimes this takes the course of agreeing with one or another scientist. A great many philosophers, for example, believe that a species is what Ernst Mayr said species – the category – are; that they are reproductively isolated groups of organisms. Other philosophers will accept some other option; it might be the ecological concept of species, or the so-called species nominalism which treats species as matters of convenience, as Darwin is supposed to have done (but didn’t) and John Maynard Smith and JBS Haldane did.
Then a philosopher might seek to synthesise several concepts to form a new one, or may even try to situate the various conceptions together in a single framework. These are second and higher order questions that one only does when one is doing philosophy.
There’s a very indeterminate line between science and philosophy. Theoretical biology, for example, often deals with these higher order questions as part of the business of forming new hypotheses. For example, in the development of methodological techniques in, say, phylogenetics, researchers will appeal to a criterion of a good inferential technique like Bayesian inference, or of good science, like verisimilitude (or “truthiness” to use a political term) or falsifiability. Often these disputes are indeed philosophical. This is unsurprising, because until fairly recently in historical terms, the enterprises of philosophy and science were considered the same.
Motivation: That’s where the cognitive action is
Why do philosophers flock around science like ants at a picnic? It’s the same reason – that’s where the sugar is. Philosophy is in large part concerned with knowledge, and the most active knowledge gathering is, and has been for four centuries or so, science. Nothing else has come close through human history. Four hundred years ago we thought water was watery form imposed on a neutral substance; now we are manipulating the basic building blocks of matter and converting elements into other elements. We can take genes from one “kingdom”, say insects, and place them in another to make luminous plants. While there are other forms of knowledge gathering, such as economics and literature, none of them can tag active genes or make a polymer that never existed before.
So it is something to know, how we know. And why it works. And if it will work in the future, and so on. That’s the next post.