Fundamentality and anthropocentrism

Say an object is grue if it is observed before the year 2100 and green, or it is blue but not observed before 2100. Then it is reasonable to do induction with “green” but not with “grue”: our observations of emerald color fit equally well with the hypotheses that emeralds are green and that they are grue, but it is the green hypothesis that is reasonable.

A plausible story about the relevant difference between “green” and “grue” is that “green” is significantly closer to being a “perfectly natural” or “fundamental” property than “grue” is. If we try to define “green” and “grue” in fundamental scientific vocabulary, the definition of “grue” will be about twice as long. Thus, “green” is projectible but “grue” is not, to use Goodman’s term.

But this story has an interesting problem. Say that an object is pogatively charged if it is observed before Planck time 2ⁿ and positively charged or it negatively charged but not observed before Planck time 2ⁿ. By the “Planck time”, I mean the proper time from the beginning of the universe measured in Planck times, and I stipulate that n is the smallest integer such that 2ⁿ is in our future. Now, while “pogatively charged” is further from the fundamental than “positively charged”, nonetheless “pogatively charged” seems much more fundamental than “green”. Just think how hard it is to define “green” in fundamental terms: objects are green provided that their emissive/refractive/reflective spectral profile peaks in a particular way in a particular part of the visible spectrum. Defining the “particular way” and “particular part” will be complex—it will make make reference to details tied to our visual sensitivities—and defining “emissive/refractive/reflective”, and handling the complex interplay of these, is tough.

One move would be to draw a strong anti-reductionist conclusion from this: “green” is not to be defined in terms of spectral profiles, but is about as close to fundamentality as “positively charged”.

Another move would be to say that projectibility is not about distance to fundamentality, but is legitimately anthropocentric. I think kind of anthropocentrism is only plausible on the hypothesis that the world is made for us humans.