@Justin,
Haha! Give that man a cigar!!
Yes, Justin.
Baruch (Benedict) Spinoza (1623-1677), Dutch pantheistic philosopher. Ethics, bk. V, prop. Xlii, On the Improvement of the Understanding, the Ethics, and Correspondence, pp. 270-271, trans. by R.H.M. Elwes, Dover, New York (1955).
Very impressive indeed!! However did you know that? For I left scant clues.
Anyway, it's Justin's turn now.