calimac

I think you misunderstood the commenter. S/he (but probably he) did not say Heinlein "taught me to think for myself," but "ways to think for myself". Heinlein in various places and in various ways told us to get the facts first, that facts trump opinions, and that stupidity will get you killed. I posit that things like this, rather than the specific things he suggested we think (some of which were, imio, horrendous, others outrageous but interesting) that your commenter was referring to.