Panpsychism is the belief that mind is the fundamental stuff of the universe. According to panpsychism, very simple things – cells and subatomic particles, not to mention rocks and stones and trees – have experiences. Perhaps they are sentient or possess rudimentary consciousness. If panpsychism is right, then the ‘mystery of consciousness’ is no mystery at all, but a basic fact about the world. This is an idea with a long, though rather marginal, history in the Western tradition.

Before the internet, I owned a four-volume hardbound set of books entitled simply The Encyclopedia of Philosophy, published by Macmillan in 1967. The entry for panpsychism reads, in its entirety: ‘see animism.’ Animism, as described by E. B. Tylor in his pioneering 1871 book Primitive Culture, is the conviction that natural objects possess souls or spirits. Tylor ascribed this belief to primitive peoples. That brief entry in the Encyclopedia of Philosophy thus reveals a great deal about the philosophical respectability of panpsychism in the middle of the twentieth century.

But things have changed. The invaluable online Stanford Encyclopedia of Philosophy has an 11,000-word essay on panpsychism, written in 2017 and filled with learned distinctions and subtle tweakings of the idea: constitutive versus emergent panpsychism, pan-experientialism, panprotopsychism, and so on. Meanwhile, a search for ‘animism’ in the Stanford Encyclopedia yields entries on environmental ethics,childhood, Japanese philosophy, and feminist philosophy of science – but nothing on panpsychism. Clearly, panpsychism's fortunes have risen dramatically in the world of professional philosophy. (If further proof were needed, there is now a Routledge Handbook of Panpsychism, published in 2020.) But respectability has come at the price of severing the association with animism, a concept of interest to anthropologists and environmentalists and feminists but apparently not to serious analytic philosophers.

What are we to make of the tangled relationship of these two words? Contemporary panpsychists, now housed in reputable departments of philosophy, might choose to distance themselves from the association with primitivism and religion – to say, in effect, ‘that's not what I mean by panpsychism!’ But those with more historical or literary inclinations might choose to dwell on the tendency of the two terms to show up together.