Scepticismcan never be thoroughly applied, else life would come to a standstill.

In so complex a thing as human nature, we must consider it is hard to find rules without exception.

I take a dose of mathematics every day to prevent my brain from becoming quite soft.

You should read history and look at ostracism, persecution, martyrdom, and that kind of thing. They always happen to the best men, you know.

It is well known to all experienced minds that our firmest convictions are often dependent on subtle impressions for which words are quite too coarse a medium.

Uncomfortable thoughts must be got rid of by good intentions for the future.

Your dunce who can't do his sums always has a taste for the infinite.