Pythagoras, Plato and everything

Scientific American: Letters ix isla Oamenàes Give us your opinion. AMERICAN.com Page 1 of 2 PCAID > Complete ourbriefsurvet eb ttt EL July 8, 2C ar LETTERS TO THE EDITORS June 17, 2001 Advanced Search TODAY'S NEWS - enter email Letters = EXPLORE «previous 1 2 ASK THE EXPERTS QUICK POLL PYTHAGORAS, PLATO AND EVERYTHING | Subscri FEATURE ARTICLES EXHIBITS INTERVIEWS TECHBIZ NANOTECHNOLOGY CURRENT ISSUE UPCOMING ISSUE PAST ISSUES SCIENTIFIC AMERICAN If a “theory of everything” ["100 Years of Quantum Mysteries,” by Max Tegmark and John Archibald Wheeler] were to be totally mathematical, with "no concepts at all,” perhaps the best interpretation of this would be Pythagorean. That is, to date we have assumed that the mathematics describes some reality that is going on; this has led to all sorts of mental gymnastics about what electrons and the like are "really" doing between observations—gymnastics that have gotten us into all kinds of trouble, not to mention many-worlds, consistent histories, “rampant linguistic confusion" and even Zen. All this results from assigning a descriptive role to mathematics. Perhaps, following Pythagoras, we should assign a prescriptive role to the math: assume the equations are real and that matter is formless and comports itself in accordance with them. That is, the equations do not describe what matter does; rather, they tell it what to do. ALBERT S. KIRSCH Brookline, Mass. Tegmark replies: With such a viewpoint, which might also be termed Platonic, the mathematical structure encapsulated by the equations wouldn't merely describe the physical world. Instead this mathematical structure would be one and the same thing as the physical world, and the challenge of physics would be to predict how this structure is perceived by self-aware substructures such as ourselves. IN FORESTS, THE OLDER THE BETTER |__Bookest: | Ss Buy on for $5.1 SAVE 16% ofi 7 CIENTIFIC. ‘S E AMERICAN Several points made in “Debit or Credit?” by Sarah Simpson [News and Analysis] lose sight of the fact that forests can contribute legitimately to lasting reductions in atmospheric carbon dioxide. We can continue to newsstand f manage forests in the usual fashion globally (where deforestation is the SPECIAL SEC second-largest source of CO2) and nationally (where the forest sink has SWEDIS been declining for the past decade), or we can take the positive steps BIOTE envisioned in the Kyoto Protocol, which calls for the maintenance and enhancement of existing forests. Significant and long-lasting gains can be C NOW made by reducing carbon emissions from deforestation and by enhancing carbon stocks through maintaining older forests. In the next 50 years these gains will be far larger than those from newly planted forests. SANDRA BROWN Winrock International Corvallis, Ore. LAURIE A. WAYBURN President, Pacific Forest Trust Santa Rosa, Calif. Letters to the Editors Scientific American 415 Madison Ave. New York, NY 10017-1111 ../article.cfm ?articleID=00075 1 F 1-E286-1C6F-84A9809ECS88EF2 1 &pageNumber=2&cat!7/8/2002