“I shan’t learn mathematics, sir. I shall not learn it. My father wants me to learn mathematics but I cannot and I shall not learn it. I have no interest in mathematics and I have no aptitude for it, sir. No mathematical aptitude, do you understand? My father puts far too much faith in mathematics, too much faith in it and too much emphasis on it, my father has altogether too much mathematical faith, sir, and if he expects that we will one day communicate mathematically, he is mistaken. I shall not learn mathematics. Perhaps at one time I could have learned it, I used to be clever, I used to be a clever person, but now I cannot learn it, now I am a stupid person, now I am a crazy person, my mind no longer functions as it ought to. My sisters have much more mathematical aptitude than me, they should have been me and I should have been them, yes, I should have been my sisters! That I should’ve been my sisters and my sisters me is a thought that often recurs to me. Father must not make me do mathematics, Father must allow me to be mad. Please inform my father of this, that if a mathematics tutor, in his capacity as a tutor, were to step foot in this turret, that tutor, in this turret, even before he attempts to impart to me the most elementary theorem, the most intuitive axiom, would be straightaway torn apart at the joints, a message for my father. I would pluck out the tutor’s eyes, I would cut off the tutor’s ears, I would tear out that tutor’s tongue also. I thank you for the orange, sir, but I shan’t learn mathematics. No, no, I shall not learn it.”

And with that Prince Heinrich withdrew to the farthest and darkest corner of his turret.

THE ASTRONOMER PEERED into his telescope.

“The bodies are aligning exactly as they should,” he said, according to Leibniz. There were eighty minutes till the predicted eclipse. Through the warped slat the sliver of sky was still bright and blue. The astronomer said: “The darkness will be very brief but it will be very dark, so dark that of the three of us only Linus will be able to see. The domestic cat is capable of seeing in conditions of considerable darkness.”

And he picked up his quill and wrote something down.

HE HAD, NATURALLY, no intention of ever returning to that turret, much less stepping foot inside it.

Nothing, he felt, could make him do that, not even a commandment from the mouth of the Emperor.

Yet the following day would find him on his knees before its door begging for entrance.

Leibniz: And what could compel you to do such a thing?

“The stars compelled me,” the astronomer said, peering into his telescope. “Listen.”