Last week I pondered the question "at what point is a writer committing plagiarism, and at what point is he using already-known information in his own words? Is it a matter of mixing up ones words a standard amount?" I asked Richard Wald, professor at Columbia University's School of Journalism, his thoughts on the subject and he got back to me yesterday.

I guess I would break it down into some constituent parts. The first is simply legal. In law, you cannot copy more than a "fair use" of someone else's material. The law is written so that reviewers can show samples or someone can quote another's work. The extent of allowed copying is a little vague. It is supposed to be incidental to the main work. Theoretically, you'll know if it's too much when you read it or see it on your TV screen, or get sued.

The second is in standard works. If you use the information in the almanac, I do not think you are plagiarizing. People usually attribute the source because if it is wrong, they want to pin the blame somewhere else --but I guess it would be ok if you simply lifted the rather dull language & used it.

The third is wire service copy or pictures that are sold with the express permission to use them as the publication sees fit. Lifting a statement of fact from an AP story is ok --unless, once again, you want to pin the blame somewhere else if it is wrong. Most people just lift.

After that, things get a little tricky. I think you ought to ask a lawyer who specializes in this sort of thing. But there are kinds of plagiarizing that are not just copying out the words. Stealing someone's idea or point of view or insight into something without attribution is plagiarism, whether it is illegal or not. As a sort of off-beat example: there is a poem by Dylan Thomas that begins: "The force that through the green fuse drives the flower..." talking about a way to see the energizing, life-affirming power of nature. Suppose you were writing prose about how , in everything you see around you, there is some kind of energy and you wrote, "there is a kind of push that nature gives us, look at the way it forces a flower out of the stem, that is the energizing principle of nature." Well, it's not exactly plagiarism, but if you didn't think of it yourself --and I know you, Madam; you did not think of it yourself-- it's a kind of plagiarism.

On the other hand, sometimes there are ideas in the air and you don't know where they came from. You can see it from time to time in popular, newly-minted, clichés. "He has too much attitude." "Attitude," is what the Colbert Report has. It's in the air. Someone first used the term as an insight, a way of describing someone. It got picked up. There is an author. But there is no plagiarism. Nor is there plagiarism in common fact. If you say "a cell usually has a nucleus," you don't have to ascribe the idea to its author.

So where do I come out? Don't cheat. You can usually disguise plagiarism of ideas (although there have been powerful law suits about ways in which an author or a scientist used one idea after another, stolen from someone); it is harder to disguise plagiarism of words or music (there's always a case somewhere about someone suing the composer of a popular song because 'I had that lyric/music first') but the best defense is to have better humans not stronger laws.