Many, says Locke, suppose that there are innate ideas which the soul receives coetaneous with its origin, and brings with it into the world. In order to prove that these ideas are innate, it is said that they universally exist, and are universally valid with all men. But admitting that this were so, such a fact would prove nothing if this universal harmony could be explained in any other way. But men mistake when they claim such a fact. There is, in reality, no fundamental proposition, theoretical or practical, which would be universally admitted. Certainly there is no such practical principle, for the example of different people as well as of different ages shows that there is no moral rule universally admitted as valid. Neither is there a theoretical one, for even those propositions which might lay the strongest claim to be universally valid, _e. g._ the proposition,—“what is, is,” or—“it is impossible that one and the same thing should be and not be at the same time,”—receive by no means a universal assent. Children and idiots have no notion of these principles, and even uncultivated men know nothing of these abstract propositions. They cannot therefore have been imprinted on all men by nature. If ideas were innate, then they must be known by all from earliest childhood. For “to be in the understanding,” and “to become known,” is one and the same thing. The assertion therefore that these ideas are imprinted on the understanding while it does not know it, is hence a manifest contradiction. Just as little is gained by the subterfuge, that these principles come into the consciousness _so soon_ as men use their reason. This affirmation is directly false, for these maxims which are called universal come into the consciousness much later than a great deal of other knowledge, and children, _e. g._ give many proofs of their use of reason before they know that it is impossible that a thing should be and at the same time not be. It is only correct to say that no one becomes conscious of these propositions without reasoning,—but to say that they are all known with the first reasoning is false. Moreover, that which is first known is not universal propositions, but relates to individual impressions. The child knows that sweet is not bitter long before he understands the logical proposition of contradiction. He who carefully bethinks himself, will hesitate before he affirms that particular dicta as “sweet is not bitter,” are derived from universal ones. If the universal propositions were innate, then must they be the first in the consciousness of the child; for that which nature has stamped upon the human soul must come into consciousness antecedently to any thing which she has not written there. Consequently, if there are no innate ideas, either theoretical or practical, there can be just as truly no innate art nor science. The understanding (or the soul) is essentially a _tabula rasa_,—a blank and void space, a white paper on which nothing is written.