If another Messiah was born he could hardly do so much good as the printing-press.

He who is in love with himself has at least this advantage - he won't encounter many rivals.

The more experiences and experiments accumulate in the exploration of nature, the more precarious the theories become. But it is not always good to discard them immediately on this account. For every hypothesis which once was sound was useful for thinking of previous phenomena in the proper interrelations and for keeping them in context. We ought to set down contradictory experiences separately, until enough have accumulated to make building a new structure worthwhile.

Delight at having understood a very abstract and obscure system leads most people to believe in the truth of what it demonstrates.

If we make a couple of discoveries here and there we need not believe things will go on like this for ever. Just as we hit water when we dig in the earth, so we discover the incomprehensible sooner or later.

To make astute people believe one is what one is not is, in most cases, harder than actually to become what one wishes to appear.

The course of the seasons is a piece of clockwork, with a cuckoo to call when it is spring.