Why shouldn't I think that humans are just hard-wired to pull a hand back from the fire.

After all, plenty of materialist, scientist minded people seem to deny that consciousness (the knower of pain) is any more than an epiphenomena of electro-chemical activity in the body-mind-sense-complex that we call "I" or me.

If consciousness is only an add-on to the fundamentally real and thus dispensable, there is no difference between lobster and man except the complexity of their feelings, fantasies and dreams.

All life is sentient, in my opinion-understanding. All life forms are aware of their environment and I doubt that only higher life forms seek to avoid discomfort and pain due to feelings rather than programming.