Sometimes I wonder whether I, or any real scientist, can be considered a “materialist” any more. That is, do I really think that matter – chunks of solid ‘stuff’ – is all there is? Here is a quote from Richard Dawkins’ The God Delusion which may help clarify (or further confuse) the issue:

We have this tendency to think that only solid, material “things” are “really” things at all. “Waves” of electromagnetic fluctuation in a vacuum seem “unreal”. Victorians thought that waves had to be waves “in” some material medium. No such medium was known, so they invented one and named it the luminiferous ether. But we find “real” matter comfortable to our understanding only because our ancestors evolved to survive in Middle World, where matter is a useful construct.

Now, perhaps my definition of “matter” here is too limited. Surely matter is more than the solid chunks our brains are programmed to understand, and must also include things like photons and gravity. Even then, though, there are weird exceptions that are certainly real but can hardly be said to fit into the label of “material”. For example, quantum entanglement allows two distant photons to be related to each other in a predictable way. But is the nonlocal connection between them really “material”? What about concepts like “memes” – cultural ideas that are passed from person to person? They are real things, which have effects on the material world of our brains and behaviour, and exist in material manifestations, but what about the meme itself? A pattern of information – an idea – can take material form, but is not itself material, is it?

We can broaden our definition of material to include anything that affects or interacts with the observable world. But then how are we any different than dualists, who say that there is an immaterial “soul” which affects (perhaps through the pineal gland), but is not really part of, the material brain?

I dunno. Now I’ve confused myself. Maybe it’s best to leave labels like “materialist” out of science and let the evidence lead us wherever it goes, whether it fits our previous definiton of “material” or not.