Geological reductionism

One way for a naturalist to respond to arguments from, say, morality (such as this argument) is to either deny that our moral perceptions are veridical or to reduce the moral to the non-moral, say to a sentiment.

One should see moves that deny the veridicality of a large class of our perceptions (illusionism), or that reduce apparently objective truths to subjective ones, as epistemically costly. One way to see this is to consider parallel responses that a straw man young earth creationist might make to geological arguments:

1. Illusionism: Of course, the earth looks like it's billions of years old, but that appearance is non-veridical, being the result of Satan's work at deceiving us into thinking creationism is false.
2. Reduction: If t is more than 10000 years ago, to affirm that a geological state S of affairs occurred at t is just to affirm that right now it looks as if S occurred at t.

On the correct epistemology, moves such as these should be quite costly. (The above are only straw man versions of young earth creationist responses. In fact, apparently the Satan response is in disrepute among young earth creationists and I have never heard anybody make the reduction response.)