Loosely, "even more so" or "with even stronger reason". Often used to lead from a less certain proposition to a more evident corollary. It is unwise to invest in pyramid schemes, and, a fortiori, in e-mail pyramid schemes.
Monday, 5 March 2007
Affair of the diamond necklace
She became impatient with the jeweller and snapped, "Not only have I never commissioned you to make a jewel … but, what is more, I have told you repeatedly that I would never add so much as another carat to my present collection of diamonds. I refused to buy your necklace for myself; the king offered to buy it for me, and I refused it as a gift. Never mention it again."