Man, being the servant and interpreter of Nature, can do and understand so much and so much only as he has observed in fact or thought of the course of nature; beyond this he neither knows anything nor can do anything.

It is idle to expect any great advancement in science from the superinducing and engrafting of new things upon old. We must begin anew from the very foundations, unless we would revolve for ever in a circle with mean and contemptible progress.

Generally, youth is like the first cogitations, not so wise as the second. For there is a youth in thoughts, as well as in ages. And yet the invention of young men, is more lively than that of old; and imaginations stream into their minds better, and, as it were, more divinely.

It is in life as it is in ways, the shortest way is commonly the foulest, and surely the fairer way is not much about.

It's such an extraordinary supple medium that you never do quite know what paint will do.

I want a very ordered image, but I want it to come about by chance.

I like, you may say, the glitter and colour that comes from the mouth, and I've always hoped in a sense to be able to paint the mouth like Monet painted a sunset.