By 1990 the research environment was saturated with computers, and only then did further gains manifest in increased power rather than numbers. Mobile robot research might have blossomed sooner had the work been done on supercomputers, but pointlessly. The opinion remained defensible in the 1970s, as reasoning and game-playing programs performed at modest human levels. With the best programs, single images crammed memory, simply scanning them consumed seconds, and serious image analysis took hours. Human vision performed much more elaborate functions many times a second.
Computers calculate using as few gates and switching operations as possible.
Human calculation, by contrast, is a laboriously learned, ponderous, awkward, unnatural behavior. Tens of billions of neurons in our vision and motor systems strain to analogize and process a digit a second. If our brain were rewired into 10 billion arithmetic circuits, each doing 100 calculations a second, by a mad computer designer with a future surgical tool, we'd outcompute 1 MIPS computers a millionfold, and the illusion of computer power would be exposed. Though spectacular underachievers at the wacky new stunt of longhand calculation, we are veteran overachievers at perception and navigation. Our ancestors, across hundreds of millions of years, prevailed by being frontrunners in the competition to find food, escape danger and protect offspring.