If the primary qualities are in bodies, and thus are similar to the ideas we have, secondary qualities are not really in things, and ideas that we do not correspond to reality.
To better understand this idea, Locke is an example: “This is sweet, blue or hot in the idea is nothing in the body which we give these names a certain size, shape and particle motion insensitive which they are composed.
Nevertheless, some principles are universally recognized. Can you imagine them to be because of their innate character?
Locke questions the existence of universal principles.
Locke distinguished in the Essay on Human Understanding two kinds of ideas: ideas simple and complex ideas.
Simple ideas are mixed in the sensible object perceived. He understands that the white and cold snow are distinct qualities simple: “nothing is more obvious to a man that clear and distinct perception he has of those simple ideas.” These are “all the materials of our knowledge.” The mind can combine these simple ideas, and make complex ideas “when the mind has once received these simple ideas, it has the power to repeat, compare, to unite them together with an almost infinite variety , and thereby to form new complex ideas.” However, it can create for himself new simple ideas.Care must be taken to distinguish the ideas in the mind and the qualities in bodies, “material modifications that produce these perceptions in the mind.” It should not, in fact, “we figured (as it is perhaps too accustomed to do so) that our ideas are real images or resemblances of something inherent in the subject that produces them.” In fact, “most of the ideas of sensation in our minds no more like something that exists outside of us, the names are similar to our ideas.” The author of the Essay Concerning Human Understanding provides a definition of the idea as “a perception that is in our mind when he thinks.” While the quality of the object is “the power or faculty that has to produce a certain idea in mind.” A distinction that has been made between idea and quality, Locke proposes a second: that between primary qualities and secondary qualities The primary qualities are those that are “wholly inseparable from the body in a state it is, so it keeps them always, any change or alteration that the body comes to suffer.” They are in “every part of matter.” This is the extent, strength, shape, motion, number. Coupons a grain of wheat in two: each party has always a certain extent, some form, etc..Trying to reverse our eyes and make the understanding itself the subject of our review.Perhaps this will allow us to determine “the certainty and extent of human knowledge”.These qualities produce in us simple ideas, when we perceive them.Secondary qualities are those things in “the power to produce various sensations in us by means of their first qualities [range, size, etc.].” 1. The qualities come knocking our senses by the action of a particle insensitive.In the first book, Locke attacks the doctrine of innate ideas, found in Descartes.This doctrine says that man is born with ideas already formed in the mind, like God, as he argues in his Meditations.Locke devotes an entire chapter of the Essay Concerning Human Understanding practice principles, to show that none of them is therefore innate universal.Indeed, if morality was innate, we would all moral, and we would all have pangs of conscience for violation of murder or theft, which is not the case.