““Those who suppose they are producing a materialist theory of knowledge when they make knowledge a passive recording and abandon the “active aspect” of knowledge to idealism, as Marx complains in the theses on Feuerbach, forget that all knowledge, and in particular all knowledge of the social world, is an act of construction implementing schemes of thought and expression, and that between conditions of existence and practices or representations there intervenes the structuring activity of the agents, who, far from reacting mechanically to mechanical stimulations, respond to the invitations or threats of a world whose meaning they have helped to produce.””
![“The main defect of all hitherto-existing materialism — that of Feuerbach included — is that the Object [der Gegenstand], actuality, sensuousness, are conceived only in the form of the object [Objekts], or of contemplation [Anschauung], but not as human sensuous activity, practice [Praxis], not…” quote by Karl Marx](https://sms4smile.com/quotes/img-quotes/49d/karl-marx-399_1st-theses-on-feuerb_the-main-defect-of-all-hitherto-existing_1877463.jpg)
![“I never knew any man who had once tasted the sweetness of experimental knowledge, that ever afterward fasted after ye Vapour garlick and onions of phantasmatical seeming philosophy." [William Petty]” quote by Carl Zimmer](https://sms4smile.com/quotes/img-quotes/e5a/carl-zimmer-16331_knowledge_i-never-knew-any-man-who-had-once-tasted_1770.jpg)
