Earth Philosophy

Earth Philosophy

The planet we call Earth has specific properties, physically and geologically. It is reasonable to suppose that all of life reflects these properties—physiologically and psychologically. It is also reasonable to suppose that human science is imbued with these properties; on other planets with intelligent life forms the science may be quite different. A totally liquid or gaseous planet might produce a different sort of science, there being no solid objects there (the scientists have liquid or gaseous brains).[1] There may be overlap with our science, but there won’t be identity. If these beings have evolved very differently, owing to the environmental difference, the departures from human science may be quite marked. Call this “planet-relativity” (it doesn’t imply relativism about scientific truth). The content of science is environment-dependent. But is the same thing true of philosophy? At first, I think the inclination is to say yes: philosophy too is planet-relative. Aliens will or may do philosophy differently from us. They have different problems and entertain different answers to those problems. They may not be so hung up on substance ontology and more receptive to ontological variety (their paradigm of the physical may be a volume of gas or a force field). But on reflection I think this is not so: philosophy will have a certain universality. For the problems of philosophy transcend environmental particularity. There will be an external world problem and a free will problem and a mind-body problem and an ethical realism problem. These problems employ highly abstract concepts that generalize across planets and habitats—mind-independence, determinism, subjective and objective, ethical variation across space and time. Philosophy is not concerned with this planet, or even this universe, in the way science is (“earth science”). Biology wants to know how life evolved here, but philosophy wants to know if free will is possible anywhere. It is concerned with possible worlds not local planets (or even galaxies). Philosophy is planet-independent. Thus, science is empirical in this sense, since it focuses on what is observable in this universe; but philosophy is super-empirical in that it tries to get beyond local phenomena. This is why it is so concerned with necessary truth—the kind that is not planet-relative (or even universe-relative). It seeks absolute generality; not just an absolute conception of this universe but of any universe. If philosophy were ever to solve the problem of mathematical truth, the solution would hold for all possible thinking beings in all possible worlds, no matter what planet these thinkers are from (it isn’t about the nature of mathematical truth here). The laws of gravitation may not hold in all sectors of our universe, still less all possible universes, but the laws of arithmetic do; they don’t vary with the physical environment. Nor is it possible for freedom to be compatible with determinism here but not elsewhere, or for the mind to be the body in Alpha Centauri but not in the Milky Way. Ethics is not objective on Earth but subjective on Mars. Philosophy is then different from the other sciences: it isn’t variable across planets and intelligent beings. Philosophical interests may vary, but not philosophical problems and truths. This makes it special. I don’t mean superior, though that may be argued; I just mean sui generis. It is a different kind of subject. A university science curriculum may be very different in another galaxy or possible world, but the philosophy curriculum will be much the same. You could get a job there in philosophy, but the science departments will never hire you (“All he knows is earth chemistry”).[2]

[1] You can find this question entertainingly discussed in Do Aliens Speak Physics? by Daniel Whiteson and Andy Warner (2025). I appear cartoon-like on page 228.

[2] I think this explains a lot about the experience of doing philosophy as opposed to science; it feels capacious, transcendent, nonlocal. It feels BIG.