One's first step in wisdom is to question everything; one's last is to come to terms with everything.
The fly that doesn't want to be swatted is most secure when it lights on the fly-swatter.
Too much is unwholesome.
Never undertake anything for which you wouldn't have the courage to ask the blessings of heaven.
If we thought more for ourselves we would have very many more bad books and very many more good ones.
...if we gained only one incontestable truth every ten years from each of our philosophical writers the harvest we reaped would be sufficient.
What I do not like about our definitions of genius is that there is in them nothing of the day of judgment, nothing of resounding through eternity and nothing of the footsteps of the Almighty.
It is almost impossible to carry the torch of truth through a crowd without singeing somebody's beard.
The most dangerous of all falsehoods is a slightly distorted truth.
Man…who lives in three places – in the past, in the present, and in the future – can be unhappy if one of these three is worthless. Religion has even added a fourth – eternity.
Many are less fortunate than you’ may not be a roof to live under, but it will serve to retire beneath in the event of a shower.
Aujourd'hui, on cherche partout à répandre le savoir; qui sait si, dans quelques siècles, il n'y aura pas des universités pour rétablir l'ancienne ignorance?
Nothing puts a greater obstacle in the way of the progress of knowledge than thinking that one knows what one does not yet know.
Where the frontier of science once was is now the centre.
A book is a mirror: if an ape looks into it an apostle is hardly likely to look out.
A book is a mirror; if an ass peers into it, you can't expect an apostle to peer out.
When a book and a head collide and a hollow sound is heard, must it always have come from the book?
Libraries can in general be too narrow or too wide for the soul.
There is no mistaking a good book when one meets it. It is like falling in love.
