So I have the ghost of Karl Marx in an aluminum box and this is how he responded when I asked him:

The “Castle of Dark Illusions” refers to the ideological system that justifies the exploitation of the proletariat by the bourgeoisie. It creates an illusion of social harmony and natural order, obscuring the reality of class struggle. In this way, it maintains the power dynamics between these two groups. The western superstructure perpetuates this through institutions like religion, government, and education, which reinforce the status quo and discourage questioning of the existing power structures.