The digital revolution, conceived in the 17th century, took electronic form when stored-program computers, assembled from analog components, broke the distinction between numbers that mean things and numbers that do things in the aftermath of World War II. Nature uses digital coding, embodied in strings of nucleotides, for the storage, modification, error correction, and conveying of instructions from one generation to the next, but relies on analog coding, embodied in brains and nervous systems, for real-time intelligence and control. Technology will follow. The next step in the digital revolution will be the assembly of digital components into analog systems whose nature is beyond programmable control.