John J. Hopfield

Professor of Molecular Biology, Princeton University

Most Important Technology of the Last 40 Years:

The integrated circuit.

Most Important Technology for the Coming Decade:

Nanotechnology.

Technology That has Evolved in a Surprising Way:

Superconducting elements for computers—it just never went anywhere.

"To understand how you think, you have to describe what the brain is doing in mathematical and physical terms. Biology is doing some form of computing on some kind of hardware—we call it wetware, hardware made out of mushy stuff. That's how you understand how a computer works: you have to understand how the algorithms fit on the hardware. A psychologist is in some sense trying to understand how the nervous system carries out algorithms. One of the things that brings biology and engineering together is wanting to understand how things work and what parts are there because they have a function. Evolution and the cost-conscious engineer will both have the thought, 'I want to do this economically.' "