These words pertain to various political theories that propose the government ownership of a country’s means of production. Socialism , in its generic sense, is a term of neutral force under which to group all such philosophies, but the word is blurred at the outset in that the adherents of many of these systems will argue that only their particular philosophy is the "true" socialism . On the other hand, advocates of an opposing economic system, capitalism, use the word socialism in an equally inexact way ?as a general term of a nation’s economic life.

Political scientists, in attempting to keep the word useful as a neutral term of description, must cope also with the fact that socialism has been used to describe both democratic and totalitarian systems. The first of these uses applies to the politico-economic systems of such countries as Australia, Britain, New Zealand, Sweden, etc., in which democratic elective processes are combined with government welfare programmes and government control or ownership of selected industries. This specific meaning of socialism (often called democratic socialism) is brought into play as a means of contrasting these countries with those commonly thought of as communist and in which free, elective representative government is not maintained.

Collectivism is a generic term that is useful because it does not contain the ambiguities inherent in the word socialism . It refers, not to a particular systematic ideology, but rather to any tendency towards the centralizing or power in the hands of a controlling bureaucracy. It can be applied with equal accuracy to any nation with a strong central government, whether democratic or totalitarian, capitalist or socialist. It is often used to the socialistic tendencies of any government ?in which case the word carries an overtone of disapproval: The century saw the rise of collectivism in all its various forms, with a corresponding decline in the importance put upon the worth of the individual.

All the remaining terms pertain to a particular kind of communism . This term itself, while the most general, is least open to a precise definition because of its constant redefinition by propagandists of all persuasions. Karl Marx and others founded Marxism , which advocated seizures of power by workers in violent revolution. Marx predicted that after this seizure the state would "wither away," leaving a perfect, classless society. Until this condition of ideal communism could be reached, post-revolutionary man would approach it through the institution of a proletarian, socialist dictatorship. Because communism is imagined as a future perfection, some communists call their present system socialism , causing much confusion to those not acquainted with Marx’s apocalyptic prophecies.

Nikolai Lenin, the first revolutionary leader of the Soviet Union, made basic changes in Marxism that gave rise to Leninism , or Marxist-Leninism as it is sometimes called. He attempted to explain why the communist revolution had succeeded first in a backward country like Russia rather than, as Marx had predicted, in one of the most developed capitalist countries. Stalin subsequently developed this argument in a strongly rationalistic direction, proposing that the interests of the Soviet state should take priority over the task of fostering revolutions in other counties. Leon Trosky challenged this position of Stalin’s, giving rise to Trotskyism , which stressed the need for continuous world-wide revolutionary activity. This dispute gave rise to the term revisionism, meaning any departure in ideology from the original tenets of "pure" Marxism . It is still widely used in intro-communist debates to refer to a communist doctrine with which the given writer or speaker does not agree.

Maoism is used to refer to the most militant present-day version of communism, as espoused by the founder of communist China, Mao Tse-tung. It specifically implies a harsh intransigence in rejecting the possibility of co-existence with capitalistic states: Young radicals seem more attracted to Maoism than to democratic socialism or even the Leninism that has evolved in the Soviet Union.

Castroism (or sometimes Fidelism ) is usually applied to the revolutionary tendency of radicals in Latin America, after Fidel Castro, the leader who established a revolutionary government in Cuba. The word carries no implication as to what brand of socialism or communism the revolutionist might prefer: He argued that Castroism could gain no foothold in those countries where genuinely democratic reforms were being made.