There are three difficulties in authorship; to write any thing worth the publishing — to find honest men to publish it — and to get sensible men to read it.

No disorders have employed so many quacks, as those that have no cure; and no sciences have exercised so many quills, as those that have no certainty.

The more gross the fraud the more glibly will it go down, and the more greedily be swallowed, since folly will always find faith where impostors will find imprudence.

Ignorance lies at the bottom of all human knowledge, and the deeper we penetrate the nearer we arrive unto it. For what do we truly know, or what can we clearly affirm, of any one of those important things upon which all our reasonings must of necessity be built--time and space, life and death, matter and mind?

Silence is less injurious than a weak reply.

With books, as with companions, it is of more consequence to know which to avoid, than which to choose; for good books are as scarce as good companions...

He that has energy enough in his constitution to root out a vice should go a little further, and try to plant a virtue in its place; otherwise he will have his labor to renew. A strong soil that has produced weeds may be made to produce wheat with far less difficulty than it would cost to make it produce nothing.