There he goes again.

Jonathan Kozol’s in town this week publicizing his new book. Its title doesn’t really even matter: Mr. Kozol does the same riffs he’s been doing in his books over decades of time.

One of them is the idea that smaller classrooms is key to good teaching. It is, mind you, just an idea — and backed up by about the same amount of evidence as the idea that cell phones cause cancer.

The main support for the smaller classrooms notion is a study done 20 years ago in Tennessee where some students were assigned randomly to smaller classes. The result? The students in smaller classes did a wee bit better than the others.

However, their performance had never been measured before they were put in the smaller classes, and so no one knew whether individual students had improved. Plus, over four years, even the itsy-bitsy improvement they had made over the students in the larger classes got no bigger.

This result was not what most of us would call revelatory. Nor was what happened in California some years later when they reduced class sizes. Barely anything happened, and what did happen was easily attributable to other improvements made at the same time.

Mr. Kozol, however, continues to pretend that the benefit of smaller classrooms is as unequivocally demonstrated as that penicillin kills bacteria, while speaking and writing against things that have been demonstrated to help kids learn.

The latest book, for example, takes the Bill and Melinda Gates Foundation to task for, of all things, supporting smaller schools. Apparently small classrooms are key, but small schools where most students are of the same race is no good because it increases “segregation.” Never mind discussions in books like Malcolm Gladwell’s “The Tipping Point,” Stephen and Abigail Thernstrom’s “No Excuses,” or Jay Greene’s “Education Myths.”

Clearly there are some issues up for discussion here. But Mr. Kozol, in his way, fights dirty.

In a radio interview this week he noted that President Bush went to Andover, where the average classroom size is 12, and that surely brown kids deserve what Mr. Bush got. That kind of populist, anti-Bush thing delights audiences, but at the expense of constructive thought.

No one disputes that education in America is in a crisis. I recall a recently overheard exchange in a Borders book store. A customer asked the clerk at the information booth, “I’m looking for ‘Animal Farm’ by George Orwell.” The clerk put down what she was doing and asked — I’m not kidding — “Okay, now what was that title again?”

That episode has occurred to me not only in illustrating that something is wrong with our schools, but in reminding me of the teachings of Orwell himself. Orwell’s “1984” imagined language being programmed in such a way that thoughts beyond those condoned by the “Powers That Be” were simply impossible to summon. Mr. Kozol, in breezily pretending that views challenging his do not exist, has created a realm rather like this among the education school crowd and beyond.

He’s not alone, of course. Just over my transom is the galleys for a book for general readers by someone who works in the same subfield of linguistics as I do. Many of his ideas are extremely controversial, but in this book, he writes as if the linguists who have challenged him barely existed.

With this guy, this is a conscious rhetorical technique. He once actually wrote to me in a letter that I was pretty smart but that there was only one big idea in our subfield, that it was his, and that he was the alpha baboon who would always be high above me in the tree.

As cuddly as Mr. Kozol is in interviews, he maintains his influence over the public conversation with an orientation not far removed from this simian one. According to him on the radio show, think tank employees writing about education are “dreary.” Never mind engaging what they write — just dismiss them in terms of their personalities.

Upon which he then recounted how embarrassed a room full of aforementioned dreary types were when a teacher stood up and informed them that six-year-olds are “leaky things.” Mr. Kozol’s voice went up a little on the word “leaky” — such cute little leakers, from their eyes when they cry and such. Aww.

The idea was, roughly, that scholarship and policy papers on education are invalid from people who have not worked with children directly. But precisely how wiping noses would improve one’s acumen with statistical analysis is unclear. Rather, Mr. Kozol was using the cute factor as a form of argumentation.

He means well, but his studious pretense that his ideas are truth rather than positions often distracts educators and writers from things that have been shown to help kids learn — such as, Egad, small schools. Here is one dreary beta baboon who feels the need to point out that people a lot older than six can leak as well.

Mr. McWhorter is a senior fellow at the Manhattan Institute.