A Terrible Road, My Son

From here this outstanding beginning:

In 1820, the Hungarian noble Farkas Bolyai wrote an impassioned cautionary letter to his son Janos:

"I know this way to the very end. I have traversed this bottomless night, which extinguished all light and joy in my life… It can deprive you of your leisure, your health, your peace of mind, and your entire happiness… I turned back when I saw that no man can reach the bottom of this night. I turned back unconsoled, pitying myself and all mankind. Learn from my example…"

Bolyai wasn't warning his son off gambling, or poetry, or a poorly chosen love affair. He was trying to keep him away from non-Euclidean geometry. Staging an intervention to keep a child out of math trouble comes off as comic to the modern reader. But in the early nineteenth century, as Amir Alexander ably demonstrates in Duel at Dawn, mathematics was viewed as a passion on par with poetry—an occupation that could lift a youth like Janos Bolyai to exalted heights, and just as quickly fling him into death or dissolution.