Dark energy is perhaps the biggest mystery in physics.

One of the nice things about problems is that a good many of them do not exist except in our imaginations.

I do not understand those who take little or no interest in the subject of religion. If religion embodies a truth, it is certainly the most important truth of human existence. If it is largely error, then it is one of monumentally tragic proportions—and should be vigorously opposed.

...we are entitled to make almost any reasonable assumption, but should resist making conclusions until evidence requires that we do so.

Civilization itself . . . can easily be swept aside when mob passions are aroused.

Sometimes things which at the moment may be perceived as obstacles-and actually be obstacles, difficulties, or drawbacks-can in the long run result in some good end which would not have occurred if it had not been for the obstacle.

To those who wish to punish others -- or at least to see them punished, if the avengers are too cowardly to take matters in to their own hands -- the belief in a fiery, hideous hell appears to be a great source of comfort.