I like both, but I've always leaned toward science fiction myself. I have an easier time finding deep and thought-provoking stories in the science fiction genre, and I tend to prefer its more emphasis on exploring what its possibilities mean and using them to examine ourselves.
There's this, and there's also I think "exploratory": what happens if you take the human condition and knock out a couple of things? Things like Left hand of darkness, and a bunch, though not all alternate history is this