Wise phrase.

“People know what they do; frequently they know why they do what they do;

 but what they don't know is what what they do does.” 

Michel Foucault.

From Wikipedia:

"Paul-Michel Foucault, generally known as Michel Foucault, was a French philosopher, historian of ideas, social theorist, and literary critic. 

Foucault's theories primarily address the relationship between power and knowledge, and how they are used as a form of social control through societal institutions. Though often cited as a post-structuralist and postmodernist, Foucault rejected these labels, preferring to present his thought as a critical history of modernity. His thought has influenced academics, especially those working in communication studies, sociology, cultural studies, literary theory, feminism, and critical theory. Activist groups have also found his theories compelling".