Human Understanding While Rene Descartes

Human Understanding

While Rene Descartes was a believer in intuitive, innate knowledge, the philosopher John Locke disputed Descartes' theories with three main arguments against innatism in his an Essay Concerning Human Understanding. Locke believed that the existence of universal assent, children and the mentally challenged, and the concept of a "tabula rasa" all prove that empirical or sensory knowledge is primary to innate knowledge.

Locke's first argument in refute of Descartes' innatism is the existence of universal assent. Universal assent is the idea that all men could reasonably agree that there are "certain principles, both speculative and practical (for they speak of both), universally agreed upon by all mankind; which therefore; they argue, must needs be constant impressions which the souls of men receive in their first beings" (Locke). However, Locke argues that there is no way to prove these universally agreed upon principles are innate. He says: "This argument, drawn from universal consent, has this misfortune in it, that if it were true in matter of fact that there were certain truths wherein all mankind agreed, it would not prove them innate, if there can be any other way shown, how men may come to that universal agreement in the things they do consent in; which I presume may be done" (Locke). Therefore, Locke argues that Descartes has no proof to his claims that universal principles must necessarily be part of man's "inherent faculties" (Locke). While Descartes insists that all knowledge gained from sensory experience after birth is deceptive and misleading, and therefore only inborn knowledge can be based on truth (Descartes), Locke argues that all men may come to universal, truthful conclusions based on sensory experience and reflection after birth (Locke).

Locke also argues against the concept of innate knowledge by referencing the existence of human beings who clearly do not understand these universal principles. Since children and the mentally disabled do not have the faculties necessary to comprehend and live by universal principles, those principles cannot be innate as Descartes believes. If they were innate knowledge, they would be understood by all men, regardless of age and intelligence. Speaking of innate and universal "truths," Locke argues: "If therefore children and idiots have souls, have minds, with those impressions upon them, they must unavoidably perceive them, and necessarily know and assent to these truths; which, since they do not, it is evident that there are no such impressions" (Locke).

Finally, Locke claims that the "blank slate" of an infant's mind, also called the "tabula rasa," offers proof that innate knowledge does not exist. As he points out, there is great variation between the painted canvasses of men's minds, all depending upon what the individual experiences, reflects upon, and chooses to give his attention to after birth (Locke). If Descartes' theory about innate knowledge is true, all men would share the same set of ideas. However, as Locke points out: "Men then come to be furnished with fewer or more simple ideas from without, according as the objects they converse with afford greater or less variety; and from the operations of their minds within, according as they more or less reflect on them" (Locke).