Page 123 - A Little Life: A Novel

encounter there would be a moment in which he wished he could disappear,
or in which he worried he might have disappointed.
One night he went to dinner at Harold’s and was introduced to Harold’s

best friend, Laurence, whom he had met in law school and who was now an
appellate court judge in Boston, and his wife, Gillian, who taught English at
Simmons. “Jude,” said Laurence, whose voice was even lower than
Harold’s, “Harold tells me you’re also getting your master’s at MIT. What
in?”
“Pure math,” he replied.
“How is that different from”—she laughed—“regular math?” Gillian

asked.
“Well, regular math, or applied math, is what I suppose you could call
practical math,” he said. “It’s used to solve problems, to provide solutions,
whether it’s in the realm of economics, or engineering, or accounting, or
what have you. But pure math doesn’t exist to provide immediate, or
necessarily obvious, practical applications. It’s purely an expression of

form, if you will—the only thing it proves is the almost infinite elasticity of
mathematics itself, within the accepted set of assumptions by which we
define it, of course.”
“Do you mean imaginary geometries, stuff like that?” Laurence asked.
“It can be, sure. But it’s not just that. Often, it’s merely proof of—of the
impossible yet consistent internal logic of math itself. There’s all kinds of
specialties within pure math: geometric pure math, like you said, but also

algebraic math, algorithmic math, cryptography, information theory, and
pure logic, which is what I study.”
“Which is what?” Laurence asked.
He thought. “Mathematical logic, or pure logic, is essentially a
conversation between truths and falsehoods. So for example, I might say to
you ‘All positive numbers are real. Two is a positive number. Therefore,

two must be real.’ But this isn’t actually true, right? It’s a derivation, a
supposition of truth. I haven’t actually proven that two is a real number, but
it must logically be true. So you’d write a proof to, in essence, prove that
the logic of those two statements is in fact real, and infinitely applicable.”
He stopped. “Does that make sense?”
“Video, ergo est,” said Laurence, suddenly. I see it, therefore it is.
He smiled. “And that’s exactly what applied math is. But pure math is

more”—he thought again—“Imaginor, ergo est.”