Over the last few days I have been reading a lot about proteins - protein structure, protein folding, how proteins interact with DNA to control gene expression. It is absolutely marvelous stuff. (It gets lonesome here, stuck with no social life in midwinter twenty-two miles from the nearest cinema).

There are two big mysteries with proteins. The first is that they're all left-handed. For some reason, all known living creatures contain only left-handed amino acids. No one has the faintest idea how this could have happened. Most people are shocked that amino acids even have hands. The creationists love it.

The second mystery in proteins is folding. Proteins start off as long strings of amino acids, like pearls on a necklace. Each pearl has a residue sticking off of it; twenty kinds of residues all together (collect them all!). As soon as you build up an amino acid string, it folds up into a complicated three-dimensional shape, full of helices, sheets, and curlicues. Some of these have great names - the jelly-roll barrel, the zinc finger.

The way the protein folds up makes sense when you look at the final shape - there are certain residues that like to touch one another, others prefer to be surrounded by water. And a given protein will always fold up the same way, spontaneously. But even for short sequences, with gigantic computers, it's impossible to predict the fold. Too many choices.

I was reading all about this second mystery, the problem of prediction, and it got me thinking about the recent predictions about the war, the economy, and everything else. It seems to be the same problem - everything looks logical in hindsight, but as soon as you try to look ahead, the number of plausible outcomes becomes overwhelming.

Of course, this lousy track record has never deterred people from making predictions. It's especially fun when you get to revisit old ones, and see how well they fared . Over at LA Weekly, they've scanned in a 1979 issue predicting what the world would be like in 2002. The first article is the best - it gets the fun things wrong:

Bobby grew up as one of the calculator toy babies of the '90s. who learned to love read-outs right in his crib. Fascinated by calculators, he has never been without one. Lately he carries a simple 30-function with a mid-range size memory.

But it also scores a home run:

Helped in part by Bobby's computer skills, the group learned to interrupt feeds from the entertainment companies and transmit their own materials. Through underground news bulletins, the Cable Phreaks managed to open the way for "guerilla" musicians and artists long ignored by the entertainment conglomerate to get their work before the public "Guerilla art," it was called, and though denounced by the L.A. Times editorial page as "juvenile" and "undemocratic," it had found a waiting audience and was being taken very seriously. Security people from AT&T and the entertainment companies, backed strongly by the FBI, were searching hard for the "guerillas"-in part because of their potential economic impact should the trend grow; in part because of federal worry about organized crime use of the codes....Only last month a San Francisco "guerilla" had been sentenced to four years in prison.

Anybody else know of good past-predictions websites? I predict that if people send in suggestions, I will post the best links next week.