"[1] Geras maintains that the concept of human nature is compatible with historical materialism, and criticized Louis Althusser and his followers for popularizing a belief to the contrary.

[2] Geras is also critical of the Hungarian Marxist philosopher István Mészáros, finding his work Marx's Theory of Alienation (1970) to be an example of the way in which Marxists have illogically denied that human nature exists even while engaging in analysis of Marx that depends on the concept of a human nature.

Geras calls Cohen's book the leading philosophical discussion of the way in which the character of human beings in any setting depends upon the nature of the prevailing social relations.

[8] Lukes found Geras's case that Marx did accept the concept of human nature convincing.

[8] The psychoanalyst Joel Kovel credited Geras with providing a thorough discussion of the Sixth Thesis on Feuerbach.