PERSON
J.J. Thomson
The experimental physicist who discovered the electron in 1897—the particle that carries every computation ever run—and who is equally instructive for the elegant model he got wrong and the extraordinary students he trained to surpass him.
Every thought a machine has ever had was carried by a particle Joseph John Thomson was the first to prove exists. When a
large language model generates a reply, the event is, at the level of physics, a vast choreography of electrons flowing through transistors—and the electron was unknown to science until 1897, when Thomson sent a beam through an evacuated glass tube, bent it with electric and magnetic fields, and concluded he was watching particles a thousand times lighter than the lightest atom. He called them corpuscles; we call them electrons; they are the reason artificial intelligence can be written at all. But Thomson is equally essential to the cycle for the two other things his career models: the plum-pudding atom, a serious and systematically wrong picture of atomic structure that his own student Ernest Rutherford destroyed with evidence, illustrating the difference between a
model that is wrong in a useful way and one defended as a creed; and