Communism of the totalitarian variety is the most destructive ideological movement in human history. Marx advocated #3 and #4 without a clear plan for how they were to be achieved, which led to Lenin's tragic idea of a dictatorship of a vanguard party (and hence #1 and #2). Vanguard party communism has led to well over 100 million democides (most of them committed by Mao and Stalin). Lenin also killed millions in his brief reign.

In my opinion, Marx's most basic mistake was one also made not only by Nazis and fascists but also by nationalists, religious Fundamentalists and state socialists: He subordinated the individual to the group. Marx wrote:

"None of the supposed rights of man, therefore, go beyond the egoistic man, man as he is, as a member of civil society; that is, an individual separated from the community, withdrawn into himself, wholly preoccupied with his private interest and acting in accordance with his private caprice..."

"Liberty is, therefore, the right to do everything which does not harm others... It is a question of the liberty of man regarded as an isolated monad, withdrawn into himself."

"The right of property, is, therefore, the right to enjoy one's fortunes and dispose of it as he will; without regard for other men and independently of society... It leads every man to see in other men, not the realization, but rather the limitation of his own liberty."

Note that, to Marx, the individual is of no importance except with reference to the group. To be moral, Marx thought, an act must not be "independent" of "society" or be taken for any selfish- even constructively selfish- reasons. This is essentially to declare the individual to be of no value, and since groups consist of individuals, any group formed on Marxist principles consists of people with mutual contempt (this does not include anarcho-communists, who aren't Marxists). The individual has to be the basis of any humane ideology since what Malcolm X said about Blacks is true of everyone:

"We cannot think of being acceptable to others until we have first proven acceptable to ourselves."

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"Some people complain about the system. The system is not good, so they can't do anything. It's an excuse. Freedom is in your heart." (Jin Xing)