The wisest man may be wiser to-day than he was yesterday, and to-morrow than he is to-day. Total freedom from change would imply total freedom from error; but this is the prerogative of Omniscience alone.

Words indeed are but the signs and counters of knowledge, and their currency should be strictly regulated by the capital which they represent.

Those that know the least of others think the highest of themselves.

It is far better to borrow experience than to buy it.

The interests of society often render it expedient not to utter the whole truth, the interests of science never: for in this field we have much more to fear from the deficiency of truth than from its abundance.

We make a goddess of Fortune ... and place her in the highest heaven. But it is not fortune that is exalted and powerful, but we ourselves that are abject and weak.

The greatest and most amiable privilege which the rich enjoy over the poor is that which they exercise the least--the privilege of making others happy.