The U. S. Constitution doesn't guarantee happiness, only the pursuit of it. You have to catch up with it yourself.

So much for industry, my friends, and attention to one's own business; but to these we must add frugality if we would make our industry more certainly successful. A man may, if he knows not how to save as he gets, keep his nose all his life to the grindstone, and die not worth a grout at last.

I am in the prime of senility.

I say it is impossible that so sensible a people [citizens of Paris], under such circumstances, should have lived so long by the smoky, unwholesome, and enormously expensive light of candles, if they had really known that they might have had as much pure light of the sun for nothing.

If you would not be forgotten, do things worth remembering.

To inquisitive minds like yours and mine the reflection that the quantity of human knowledge bears no proportion to the quantity of human ignorance must be in one view rather pleasing, viz., that though we are to live forever we may be continually amused and delighted with learning something new.

Money makes money. And the money that makes money makes more money.