Science is, I verily believe, like virtue, its own exceeding great reward. I can conceive few human states more enviable than that of the man to whom -- panting in the foul laboratory, or watching for his life in the tropic forest -- Isis shall for a moment lift her sacred veil and show him, once and for ever, the thing he dreamed not of, some law, or even mere hint of a law, explaining one fact: but explaining with it a thousand more, connecting them all with each other and with the mighty whole, till order and meaning shoots through some old chaos of scattered observations. Is not that a joy, a prize, which wealth cannot give nor poverty take away? What it may lead to he knows not. Of what use it may be he knows not. But this he knows, that somewhere it must lead, of some use it will be. For it is a truth.

Lectures on Science and Superstition.
1866.