I disagree.
Not all Leftism is based on Marxism. Admittedly, varieties of Marxism are dominant, but it isn’t the sole foundation.
Marxism has its origins also, so there can be forms of Leftism from a common ancestor - Hegel being one of them, Kant being another. Leftist academics who studied Marx digested it and then passed it on to their students as progressivism.
Marx consolidated what later became what the Left holds dear.
Many Leftists, for example, may not have reasoned it out, but give evidence in their thought that they believe in the Labor Theory of Value. That holds that rather than supply-and-demand, the value of a product is based upon how much labor was put into it. So a chair that took 4 hours to build is worth twice as much as one that took 2 hours — even if they are exactly the same in every way. Absurd, I know, but it guides many Leftist policies.
exactly, the 3 main worldviews of libtardism are marxism, secular humanism, and postmodernism.All 3 dispise Christianity.