Karl Marx is one of the most famous, if not the most famous, social intellectuals to have existed. A whole movement bears his name, and his critique of capitalism is still used to this day. But Marx was also a severe critic of the socialists of his time. In particular those who he and Engels would call the ‘utopian’ socialists. Marx saw the utopian socialists as those with their head in the sand. They wanted socialism but didn’t really know how to achieve this. Marx and Engels devised a different socialism, a scientific one.
Let us start with utopian socialism. The most important utopian socialists according to Engels were Saint-Simon, Owen and Fourier. These socialists were seen as naïve by Engels and Marx. They thought they could use the institutions of the bourgeois to usher in the era of socialism. This can be compared with present social democrats, who also try to use the institutions already in place to achieve social change. As Engels says in Socialism, Utopian and Scientific: “One thing is common to all three. Not one of them appears as a representative of the interests of that proletariat, which historical development had, in the meantime, produced.” The utopian socialists didn’t look at the material conditions of the existing society.
Marx and Engels did things differently. They weren’t going to be led by naïve fairy tales of trying to achieve socialism through the bourgeois system. Wouldn’t anything produced by the bourgeois system not just improve the bourgeois conditions? No, real socialist change could only come from the negation of capitalism, the proletariat. The rise of the proletariat was determined to overthrow the capitalist, bourgeois system according to Marx. That’s why they advocated ‘scientific’ socialism. This wasn’t because they had scientifically proven that socialism would come to pass. Marx didn’t use the scientific method to stave his framework, he kind of cherry picked the data he used in Capital. Rather they called it scientific because it was determined by Marx’s historical materialism.
History moves in a certain direction. Marx believed that history was subjected to a dialectic. Societies would come but then something else would come in its place. Material means of production constituted what society would win over the other. Capitalism was able to win over feudalism because there were better and more productive means of production. But capitalism isn’t the end stage, it is just a transfer phase to communism. This is what is called historical materialism. History progresses through the progression of material means. As the means of production evolved so would society.
Capitalism is destined to collapse according to Marx. It’s inherent into its structure. Because of Marx conception of historical materialism, it is only a matter of time before the capitalist mode of society inevitably destroys itself. I say destroy itself because Marx believed that capitalism was creating its own negation, namely the proletariat. This can be understood through Marx’s Labor Theory of Value, which is a subject for some other time. But what is important is that by continuing the capitalist way of life the proletariat would keep on increasing. It would keep increasing until it’s so big a social revolution would start which took the means of productions for themselves, for the proletariat and so the whole of man would be emancipated because the proletariat was the universal class of man. Now a classless society would exist called communism.
This reasoning I’m using is highly abridged, but I will try to explain other important points of this theory in other posts. The point I’m making is that Marx believed that the collapse of capitalism was destined and that he had proved it. The utopian socialists had no proof of turning this society in a socialist state, they were just hoping it would go that way if they tried to participate in parliament.
Now, obviously the scientific socialism that Marx and Engels tried to propose doesn’t hold any water anymore. It seems like capitalism wasn’t determined to collapse. Rather, it became bigger. Orthodox Marxism, who have a rather dogmatic approach towards Marx historical materialism, keep on hoping that capitalism will ultimately fail, and the social revolution will appear, nonetheless. It seems nowadays that utopian socialism has a better ground to stand on.
I would also say that this difference between utopian socialism and the scientific socialism of Marx, can still be seen in the present day. And it is important for critics of socialism to criticize the right socialism to the right people. If you criticize utopian socialism to a Marxist for being too idealistic, the Marxist will agree with you. If you criticize scientific socialism for being too deterministic, then the utopian socialist will agree with you. It’s always important to try and understand the other group you’re criticizing. Nothing is helped by just accepting one stance and never looking deeper into its critics.
 Friedrich Engels. “Socialism, Utopian and Scientific”.