MacTutor
4th April
On this day in 1820 Farkas Bolyai wrote to his son János about Euclid's 5th postulate:-
The postage stamp of one of today's mathematicians at THIS LINK was issued in 1971.
Do not try the parallels in that way: I know that way all along. I have measured that bottomless night, and all the light and all the joy of my life went out there.
The postage stamp of one of today's mathematicians at THIS LINK was issued in 1971.