Hypothesizing on a World Without Stars

'Well, then, supposing there were other suns in the universe.' He broke off a little bashfully. 'I mean suns that are so far away that they're too dim to see. It sounds as if I've been reading some of that fantastic fiction, I suppose.' 'Not necessarily. Still, isn't that possibility eliminated by the fact that, according to the Law of Gravitation, they would make themselves evident by their attractive forces?' 'Not if they were far enough off,' rejoined Be...