THE TWO-PARTY SYSTEM praised by conservatives, but whose evils were eloquently portrayed by H. P. Williamson in the July issue of this JOURNAL, exists in stable form in America primarily for one simple reason. This is the feature of our electoral mechanics that permits election by a mere plurality without requiring a majority. No matter how much the voter prefers the candidate and platform of a small third party to those of both the major parties, he can usually find some ground for preferring one of the major parties or its candidate to the other. Since he is virtually certain that the candidate of his first choice will not be elected, the dissident voter usually votes for that one of the two major-party candidates whom he prefers to the other. The fact that everybody does this confirms the certainty that only a major-party candidate can be elected, and perpetuates this type of political behavior through the conviction that voting for a minor-party or independent candidate means throwing away one's vote. Where, as in France, a majority is required to elect, parties multiply. If in the first election no one receives a majority, French law requires a second election. A similar situation exists in many states in this country with regard to the party primaries: if no candidate receives a majority a second primary is held, with the names on the ballot limited to the two who received the highest numbers of votes in the first primary. This system prevents the crystallization of just two stable parties or factions and maintains a fluid situation in which the voter is more likely to cast his ballot according to principle than on the basis of heredity and political organization. A related phenomenon is the essentially one-party system existing locally over large parts of the United States. The Democratic party in most southern states and the Republican party in some other regions have virtual monopolies of the chance of winning elections. The real struggle is in the primary of the dominant party, and on it, rather than on the final election, all attention is focussed. No ambitious and realistic candidate for an important public office in a southeastern state would be foolish enough to seek Republican nomination. The voters know well that the dummy Republican tickets put up