Machines in mind

Metaphors of Memory: A History of Ideas About the Mind. By Douwe Draaisma. Cambridge University Press; 270 pages; $29.95 and £18.95

MANY people fail to remember old acquaintances at one time or another. Their names might be on the tip of one's tongue, only to re-emerge, uselessly, in the middle of the night. Memory is as central to life as it is baffling to our reason. Augustine famously wondered how it was that we could remember the concept of forgetfulness.

We tend to perceive memory as a tool, external to our conscious selves. We associate it with software, say, or a storage system, partly because machines, visible and fabricated by humans, are easier to understand than ourselves. The mind is not and, some claim, could never be transparent to itself.

In “Metaphors of Memory”, a Dutch historian of psychology, Douwe Draaisma, tells the story of conceptions of memory in different ages by way of metaphors thrown up by the technology of the time. “One might wish that psychology had a better memory,” he writes, in a plea for scientists today to pay attention to ideas which preceded the advent of a recognisably modern science of the mind in the 19th century.

There has always been a link, Mr Draaisma observes, “between human memory and the means invented to record knowledge independently of that memory”—from Plato, who compared it to a wax tablet, to Freud, who likened it to a “mystic writing pad” (made out of wax paper and celluloid). To remember could be akin to minting a coin (Hugo of St Victor) or entering a storage space (Augustine). Hooke, in the 17th century, calculated how many ideas could be stored in the brain during a lifetime, borrowing from the mechanistic science of his day. At their birth, photography, the phonograph and cinematography were useful metaphors. Once Alan Turing spoke of a computer's memory, it became possible to apply computer terms to human memory.

Though too wide in scope for specialist use, this is an intellectually sophisticated book, rich in insight and detail. Mr Draaisma offers no theory of memory of his own, but his message is convincing. It is that when thinking about memory, we must realise that the material tools we use to help us remember also become the metaphors we create with our very own minds.