According to John Locke, knowledge is not innate and that all knowledge come from experiences. He believes that “ideas of colours innate in a creature to whom God hath given sight, and a power to receive them by the eyes from external objects” (Locke, 1). He presents the example of human understanding of colors is given by God. In addition, Locke denies the idea of innate principles by arguing that if there were innate ideas, then they would immediately be known to children, yet they are not. “If therefore these two propositions: ‘Whatsoever is, is;’ and, ‘It is impossible for the same thing to be, and not to be,’ are by nature imprinted, children cannot be ignorant of them” (Locke,3). On the other hand, Rene Descartes says “good sense or reason, is by nature equal in all men; and that the diversity of our opinions, consequently, does not arise from some being endowed with a larger share of reason than others” (1). He believes that everyone is equally endowed with reason, only the accidental or external parts are different.

Secondly, Descartes believes that knowledge depends on certainty. When knowledge can’t be extracted from experiences, it can be achieved by deductive reasoning similar to how mathematical proofs are derived from complex propositions. Descartes says “provided only we abstain from accepting the false for the true, and always preserve in our thoughts the order necessary for the deduction of one truth from another” (11).  In contrast, Locke says that all ideas come from sensation and reflection besides experiences. “the senses convey into the mind, I mean, they from external objects convey into the mind what produces there those perceptions. This great source of most of the ideas we have, depending wholly upon our senses” (Locke, 6). Descartes objects “neither our imagination nor our senses can give us assurance of anything” (22). He thinks that senses can be deceitful.