It is a great pity that J.B.S. Haldane, evolutionary biologist, co-founder of population genetics, and rather clever chap, was addled somewhat by ideology:
[D]ialectical materialism . . . is not merely a philosophy of history, but a philosophy which illuminates all events whatever, from the falling of a stone to a poet’s imaginings. One can only guess at what deep reasons might have led so clever a man to fall for something so shallow and foolish; but one can see quite clearly that the greatest gift to the persistence of this folly and many others is the favour of such men.
 J.B.S. Haldane, Preface to Friedrich Engels’ Dialectics of Nature, tr. C. Dutt, (New York: International Publishers, 1940), reproduced online at Marxists.org. (Elsewhere: “I have tried to apply Marxism to the scientific problems of my own day, as Engels did over many years, and Lenin in 1908 [in Materialism and Empirio-Criticism]. I do not doubt that I have made mistakes. A Marxist must not be too afraid of making mistakes.” J.B.S. Haldane, The Marxist Philosophy and the Sciences (London: Random House, 1939), reproduced online at Marxists.org, 2002.