He suggested that there are three species-wide cognitive Interests:

(1) interests in control of the physical world.

(2) understanding in the social and linguistic world.

(3) self-development and emancipation in our personal world.

(3) Justifies our desire to free ourselves from social situations that are oppressive.

Most societies have been oppressive and as such distort both our individual understanding of the world and our collective scientific knowledge. Thus individuals are not necessarily in a position to make free and rational choices.