Masaryk produced a wide range of philosophical works, including early essays on Hume, a study of the classification and interrelations of the sciences (his 1885 book) and a monumental history of Russian philosophy (1913). In epistemology he subscribed to realism (he preferred the term ‘concretism’) and was inclined towards empiricism, though he also advanced a view of cognition as a synthesis of sense perception, reason, feelings and will. Masaryk was a confirmed theist but rejected supernatural revelation as a source of knowledge.

Masaryk’s principal interest in philosophy, already evident in the 1881 study of suicide, was in its use as an instrument for the diagnosis and treatment of social ills. A believer in moral absolutes grounded in a religious perception of the world, he elaborated the humanitarian ideals that he saw as the goals of historical progress. He identified those ideals with democracy and individualism and was a stern critic of Marxism.