This is an absolute non-issue. Carson is very easily close to having an IQ close to 50 points higher than that of ultra-imbecil Walker (who might very well be even stupider than Trump, if that's even possible). Even I, who have an inmense curiousity, have no idea from where gravity comes from. In fact, that's probably the only single question here in life I've asked myself more times than the other recurring question, namely, what's the freaking meaning of life.
People say that love is the meaning of life and I believe that, yet love is something ephemeral. So basically the meaning of life is just something lasting for a few seconds of earth's life? At the very least the universe' gravity isn't ephemeral. That's the good thing about it.