Science is more like the United Nations than it is like a village. Different communities of scientists carry out their work using their own methods, languages and styles. Scientists in different fields need interpreters if they are to communicate with each other. There is no scientific lingua franca, not even mathematics.
So, while there is no incompatibility between what physics teaches us about the world and what we learn from biology, no one today would seriously propose eliminating biology by reducing it to physics. You can't carry out the work of biology — you can't identify its problems and investigate their solutions — in the language of physics.
And yet, despite this state of affairs, I suspect that many of us, and most scientists, whether they ever take the time to think about this or not, are probably committed to what I'll call the physicist's view of reality.
According to the physicist's view, it is only physics that is in the business of studying things as they really are. Physics investigates fundamental reality. What there really is, what the universe is really made up of, when you get right down to it, is what physics studies. Roughly, it's all particles — things made up of smaller things made up of smaller things made up of smaller things. (Or maybe it's all fields.)
The thing about biology, if we take up the view from physics, is that it is so very parochial. The difference between physical systems that are living and those that are not, or between chemical processes that are organic and those that are not, is not written in physics. It's an imposition or a projection, from outside, onto what are, in themselves, purely physical processes that can be entirely understood by physics.
If biology, from the physicist's point of view, is a field shaped by our characteristically human interest in life, then other sciences, like psychology, cognitive science, linguistics, anthropology and economics — which rely, fundamentally, on notions like perception, language, culture, trade, value and so on — must really look like make-believe. For there is no such thing as perception, language, culture, trade, value in the world as the physicist knows it to be.
These are not really real!
Now when I say that many of us, and most scientists, are committed to the physicist's view of reality — to the idea that physics alone describes things as they really are, apart from made-up human concerns and values — what I mean is that, if pressed, we will find ourselves tempted to say that, really, the physicist's view must be right.
Whether or not there are, or ever were, people, there would be an element with the atomic number 79. But that this element looks yellow and is soft, as far as metals go, to the touch, that it is considered rare or desirable or valuable, all this depends on the existence of creatures like us with nervous systems and social organizations like ours. Gold exists, just as it really is, just as the physicist knows it to be, and that has nothing to do with us.
Now, a worthwhile question to ask right now would be: Is the physicist's view of reality right?
There are two parts to this question. First, is there a way of knowing the world that is an encounter with things as they really are, uninfluenced by our interests, values and perceptual-and-cognitive limitations? Is there, as it has been put, a view from nowhere? Second, is this delivered, or even aimed at, by physics?
We can take it further. Granted, many of us, when pressed, will find it impossible to resist saying that the physicist's view is right. But do we really think that physicist's picture of reality is correct?
After all, we are not gods occupying a view from nowhere; we are flesh and blood; our concerns are emotional and medical and political; we are hot and cold; we experience the earth's pull on our bodies. We love and we value. Can any of us take seriously, truly, that all this might be, well, that it might be unreal?
And can we even imagine a physics that doesn't take its start from the fact that we physicists are curious people in search of good explanations? What, according to the physicist's view of reality, makes an explanation a good one, anyway?