My latest Mind and Matter column for the Wall Street Journal is on metaphors and analogies:
Monkeys can reason by using analogy, it seems. In an experiment recently reported in the journal Psychological Science, baboons in a lab proved capable of realizing that a pair of oval shapes is “like” a pair of square shapes and “unlike” a pair made of two different shapes. This finding suggests that you can have analogy without language.
The experiment, run on 29 baboons by Joel Fagot of the University of Provence and Roger Thompson of Marshall College, found that the monkeys could ignore the fact that some symbols were more familiar from previous sessions and stick with the task of selecting those that came in pairs, and that they still partly recalled the skill after a year.
Down goes another claim of human uniqueness. It had been argued that only human beings could reason by analogy because only human beings use grammatical language. Indeed, language is suffused with analogy, comprehensively infiltrated with metaphor-analogy’s sibling-to the point that we no longer notice it. (In the previous sentence, for instance, consider that “suffused,” “infiltrated,” etc. are all metaphors.)
I’ve always been especially intrigued by the way that old technologies live on as metaphors: “the horse before the cart,” “sailing close to the wind,” “the wheat from the chaff,” the hourglass that tells you a computer is thinking. We revel (ha, another one) in medieval clichés.
Does metaphor tell us something about how we reason as well as how we speak? The linguist George Lakoff has long argued that it does, that reasoning is almost a form of metaphorical thinking, that our conceptual system is primarily metaphorical. Like the baboons, we generalize by reading analogies into new situations.
Mr. Lakoff points out that certain metaphors are universal, as if reflecting shared human patterns of thought. We always compare argument to war, for instance-with words like win, lose, demolish, indefensible and attack. We relate time to money: spending, wasting, borrowing. Health, happiness and virtue are all associated with up; their opposites are down.
In his new book “The Better Angels of Our Nature” (reviewed on page C7), Steven Pinker points out that, for centuries, perpetrators of genocides have described their victims in biological terms laced with disgust: as rats, snakes, maggots, lice or diseases. This presumably helps them justify to their followers the inhuman acts they commit. Metaphors possess considerable power to move us.
Certainly, analogies can generate insights. I am fond of using one from the works of Shakespeare to explain how a mouse and a human can have mostly the same genes and yet be very different. In his plays, the bard used a vocabulary of about 20,000 words (not counting inflections like plurals), just as a mammal has about 20,000 genes. The difference between two Shakespeare plays lies not so much in the vocabulary as in the order of the words. Indeed, the six most frequent words in “Othello,” “Lear” and “Hamlet” are the same: the, and, to, of, I and you. So it is with genes: the difference between a mouse and a man is in the order and pattern of expression of the genes, not in having different genes.
Some argue that such analogical reasoning is dangerous, that your allegories can bite you if you get too close to them. Others, such as John Sowa of VivoMind Intelligence, argue that computers need to have better algorithms for finding analogies if they are ever to rival our intelligence. Analogical reasoning is good for coping with messy data, he suggests.
The 13th-century Islamic scholar Ibn Taymiyya was an early champion of such reasoning and considered it just as certain as Aristotelian syllogisms. He noted, for example, that the Koran outlaws grape wine but not date wine. Grape wine is prohibited because it is intoxicating; date wine is also intoxicating; therefore, by analogy, date wine is also prohibited.