Question: ""An Irrational System?"" Answer: ""Not So Irrational After All""--in an extended essay that might be a talk on Problems of Democracy. This is a form not frequently found in juveniles--persuasive and selective rather than didactic and comprehensive, which means that it can't be used for reference (the coverage is too incomplete, the style too discursive). Mr . Liston has done interesting offbeat books before; (Tides of Justice, Downtown); he also served as investigator for a Baltimore newspaper. Here he enlists the testimony of (necessarily anonymous) politicians on various levels and the writings of standard authorities in developing his themes; that the two-party system is stabilized by the winner-take-all principle; that politics has changed as the electorate has become better educated, more sophisticated and affluent, less bound by ethnic and special-interest loyalties--that it must now be persuaded; that there are few spoils but, as a result of increasing government regulation, many opportunities for manipulation--which makes the local boss more rather than less powerful. Also discussed is the high cost of conducting a campaign (and the mockery of corrupt practices laws); politics as a demanding, ego-rewarding way of life; and from the inside-campaign organization, strategy (""incomplete"" packaging of the candidate, an ""incomplete"" statement as his theme); tactics (advertising and public relations techniques). Some of Mr. Liston's suppositions are questionable (e.g., his insistence on the independence and skepticism of the electorate) and he disregards the generation gap in general, the commitments of young people in particular; neither does he offer any but the most tentative solutions. Overall, however, he reveals much that must be faced before seeking solutions.