6a. Materialism, dialectics and science (science)

With him [Hegel] it [dialectic] is standing on its head. It must be turned right side up again, if you would discover the rational kernel within the mystical shell. (Marx, Capital I, postface 2nd German edition.)

Nature is the proof of dialectics, and it must be said for modern science that it has furnished this proof with very rich materials increasing daily, and thus has shown that, in the last resort, nature works dialectically and not metaphysically. (Engels, Anti-Dühring, Introduction, General.)

Modern physics is in travail; it is giving birth to dialectical materialism. The process of child-birth is painful. (Lenin, Materialism and Empiriocriticism, end of chap. 5.)