Seth MacFarlane is most commonly known as the creator—and, in many cases, the voices—of the animated comedy series “Family Guy,” but he is also a lifelong science-fiction buff. He produced “Cosmos,” the 2014 reboot of Carl Sagan’s beloved series, and on Sunday will première a new live-action show, “The Orville,” in which he plays the captain of a spaceship four hundred years in the future. Earlier this week, I spoke with MacFarlane about the role of science (and science fiction) in the modern world. The interview has been edited for length and clarity.