NORTHAMPTON, MA — "I don't know much, but I know what I know," teacher Mary Cowhey reads aloud to the 13 second-graders assembled on the rug before her. "I know I gotta go - to Mexico!"

The book is "Gotta Go! Gotta Go!" by Sam Swope, about a "creepy, crawly bug" who instinctively knows the steps it must take to metamorphose from caterpillar to butterfly.

Not only do Cowhey's young charges know the "Mexico" refrain by heart, they also know all about butterflies and baby chicks, having raised both species in Cowhey's classroom. But, in the hour to come, this seemingly silly story will inspire an animated discussion about life cycles, inaccurate illustrations of wings and, ultimately, the purpose of life, with kids eagerly raising their hands like volleyball players at the net.

When two butterflies "dance" at the end of the book, Cowhey asks what that means.

"They're mating," answers Joe Bosco.

"Why don't they just say that?" asks Cowhey.

"Probably because little kids don't know what mating is," says Joe.

The concept of learned behavior versus instinct and how animals and humans know things without being taught is batted around.

But the kids aren't debating, necessarily.

If one disagrees with another, he or she must state that clearly and give the reasons why. If they agree with someone's point, they are expected to expand upon it.

"The purpose of a butterfly's life is to migrate," said Eli Christopher.

"I disagree," said Sierra Dunn. "The purpose of a butterfly's life is to reproduce."

When the purpose of a human's life was asked for, Katie Cole said: "To live, live, live!"

"To look, live, learn and laugh," Joe expanded.

"To reproduce," said Sierra. "If we didn't reproduce, there'd be only one generation."

It's been about 10 years since Mount Holyoke philosophy professor Thomas Wartenberg approached Jackson Street's principal Gwen Agna about working with teachers there on bringing philosophy to the classroom.

Two teachers - Cowhey and the late Susan Fink - were the first to take him up on the offer. The training, conducted through Wartenberg's community service learning workshops, enabled those two and others to either teach the method themselves or allow Mount Holyoke students into their classrooms for six-week stints.

Cowhey, Fink and others saw the study as a welcome break from the test-driven approach to learning. Cowhey says that students taking the MCAS are trained for speed.

"If it's hard, skip it," she says. "That may work on a test, but not in real life. In philosophy, kids learn to be patient in pursuing a question."

And many of these questions come from children's literature.

"Children's books often have rich philosophy embedded in them," said Cowhey. "Our theme last month was self-discipline, using Frog and Toad's story 'Cookies' as the departure point."

In the story, Frog and Toad take great lengths to curb their voracious cookie habit, including tying up the cookies in a box and putting the box up high out of reach. "But we can climb the ladder and take down the box from the shelf and cut the string and open the box," said Toad.

"That is true," said Frog, who finally just tosses the cookies to the birds and prides himself on his willpower.

"Willpower is a difficult concept to grasp," said Cowhey. "How can I stop myself from doing something I really want to do? ... But when you relate it to something like global warming, for instance, self-discipline can be a positive thing. You can ride a bike or walk to work. Yes, it's easy and convenient to drive a car ... but by cutting back on your driving habits, you're stopping a negative, starting a positive."

Cowhey believes that children are naturally inclined to probe and wonder.

"When kids bring in their own experiences, you get a lot of different perspectives," said Cowhey. "It does a lot to train kids in habits of mind, not taking things for granted, conceding points of agreement - listening to what the other side is saying."

Cowhey originally thought she'd shoehorn philosophical discussions into a regular "Thursday afternoon at two" slot, but soon found them "springing up all over the place like an invasive weed."

She recalled one instance when some hot and sweaty second-graders got into a tiff during recess because a child had intentionally stomped on a caterpillar. Another took umbrage and a shouting match ensued. "I couldn't very well move right into a math lesson," said Cowhey.

"They came to a different place of understanding," she said of the exchange. "Kids are taught to be thoughtful, to have an opinion, but not to defend it to the death. Philosophy helps them think and engage and reflect. If everyone had this, we'd be so much farther along in our society in terms of solving problems."

"You don't have to be a philosopher to lead these sessions," added Cowhey. "All it takes is a willingness to let a discussion go to a point not predetermined."