Tadeusz Kotarbiński was born on 31 March 1886 in Warsaw, then Congress Poland, Russian Empire, into an artist's family.

His professors were some of the most esteemed philosophers, logicians and mathematicians of his time: Kazimierz Twardowski, Jan Łukasiewicz, Władysław Witwicki and philologist Stanisław Witkowski.

In his activities, close to the left-wing and socialist groups, he was a member of the Polish Teachers' Union, being in the years 1937–1939 president of the Higher School Section.

After World War II, along with other eminent men of learning, he helped create a state university in Łódź.

Kotarbiński's ontological reism approach assumes that the only things that exist, and thus the only ontological category to be used, are individual, concrete objects (or bodies) in opposition to doctrines allowing for the existence of such categories as universals, states of affairs, properties, relations, sets, classes, mental constructs, etc.

[4] His position is considered partially descriptive in the sense that its aim is to understand relevant features of actions, but that the classifications it produces have normative objectives.

[5] Kotarbiński's contribution to the understanding of the nature of action is considered foundational for action theory (philosophy)[6] Three years after publishing A Treatise on Good Work, Kotarbiński persuaded the Polish Academy of Sciences to establish a Laboratory for General Questions of Work Organization (Pracownia Ogólnych Problemów Organizacji Pracy), later upgraded into a Department of Praxeology.