Materialism is the philosophical outlook that holds that matter is the fundamental substance of nature, and that all things, including mental states and consciousness, are a result of material interactions.
In contrast to idealism, which asserts ideas prevail over matter, materialism has proven to be, through the instruments of science, the correct philosophical outlook.
Historical materialism, later developed by Karl Marx, is a conception of history that draws inspiration from materialism. It further explains scientific socialism, which is a method of achieving a communist society though the basis of altering the material conditions of society.