(FORTUNE Magazine) – James M. Buchanan's Nobel Prize in Economic Science may help balance the budget. A professor at George Mason University, Buchanan, 67, has been part of the conservative wave of economic thought that has gained prominence during Ronald Reagan's presidency. Buchanan says that since politicians usually act in their self-interest, they need constitutional rules, such as a balanced- budget amendment, to offset pro-inflationary political pressures. The prestige of the Nobel Prize may help the cause of the amendment. Barcelona, Spain, and Albertville, France, will play host to the 1992 Olympics. Barcelona will be the site of the summer games, and the French Alpine town, the winter ones. In a tense five-hour voting session in Lausanne, Switzerland, Barcelona got the nod over Paris to give Spain its first Olympics. Albertville scored over winter runner-up Sofia, Bulgaria. With the decision to alternate summer and winter games every two years, 1992 will be the last time both take place in the same year. DWAYNE ANDREAS, 68, chairman of Archer Daniels Midland, defending Philippine President Corazon C. Aquino's efforts to negotiate with Communist insurgents: ''Communists aren't all bomb throwers. In a poor country some of the finest people are Communists.'' MURRAY WEIDENBAUM, 59, economist, on the tax reform act: ''What's so fair about eliminating the deduction for interest payments on your first car but not on your second home?'' SYDNEY BIDDLE BARROWS, 34, explaining how she got into the call girl business, in her best-seller, Mayflower Madam: ''As I saw it, this was a sector of the economy that was crying out for the application of good management skills.''