Any preschooler can tell you the pig says "Oink, oink." Steven Pinker can tell you what it says in Japanese. "It says, `Boo-boo,' " Pinker tells you in a puckish way unbefitting a professor at MIT.

And the porker says something else in Portuguese, although Pinker's not sure what.Pigs are pigs, and the multilingual pig hasn't yet been born. But Pinker uses this example to show how language is not only in the ear of the beholder, but in the brain. It's wired in, just like a software program.

Almost without the parent's eager coaching, Pinker says, the infant's babbling will turn naturally into something we recognize as the complex language around us.

Pinker is promoting his book, "The Language Instinct: How the Mind Creates Language," which many people think stands a good chance of winning a Pulitzer Prize.

A neurolinguist at the Massachusetts Institute of Technology, the 40-year-old Pinker wrote the book partly to explain to nonscientists the biological basis of learning language - but partly also to shoo off the "schoolmarms and language mavens" who, he says, have done more harm than good.

By schoolmarms he means the rule-enforcers who tell students it's an offense to ever split an infinitive. The language mavens are the William Safires and James J. Kilpatricks of the popular press.

Pinker says they're full of poppycock.

If anything, he says, the mavens and schoolmarms have made ordinarily intelligent people so self-conscious about their grammar that they overcompensate.

"That's why you hear educated people say `between she and I' rather than `between her and me.' "

For Pinker, clarity, vigor and grace count for more than blind compliance with the rules, which usually are arbitrary anyway. Slang doesn't bother him. Most of it goes away - "you wouldn't say `groovy' any more than you would wear bellbottoms" - and the rest of it, he says, energizes a language that would become stale without it.

The brain takes to spoken language naturally, he says, and adapts well enough without rules at every turn. "If the rule goes against the way people talk and the way that sounds right, maybe there's something wrong with the rule."