John Locke: A Few Arguments Against Innate Knowledge

Both Plato and Descartes appealed to the doctrine of innate knowledge. Socrates, in Plato’s dialogue, spoke of certain “true notions” which required stirring up to become knowledge. On the other hand, Aristotle disagreed that the concept of ‘innate knowledge’ was sound. He could not see how we could “possess knowledge superior to demonstration without being aware of it.” (see my posts on both Plato and Aristotle for more on this)

In An Essay Concerning Human Understanding (1689), perhaps “the first of the great English empiricists“[1], John Locke, presents a systematic case against innate knowledge, and argues for the doctrine that the senses are the source of all knowledge. In this post I will be exploring some of Locke’s arguments against innate knowledge.

We start with Locke’s summary of the innate knowledge position:

It is an established opinion amongst some men, that there are in the understanding certain ‘innate principles’; some primary notions … characters, as it were stamped upon the mind of man; which the soul receives in its very first being, and brings into the world with it.”

However, Locke argues that we have the faculties to attain knowledge without these innate principles. We have eyes, for example, which perceive colour, and it would seem strange for us to have this capacity and to still require innate knowledge of colour.

Locke then attacks what he perceives to be one of the common arguments for innate knowledge: the argument “that there are certain principles, both speculative and practical [2], (for they speak of both), universally agreed upon by all mankind“. If is the case, so the argument goes, then is seems reasonable to suppose that all people share certain innate principles.

Locke says that this argument is flawed on two counts. First, even if certain principles are universally held if does not follow that these principles are innate. There could be other explanations why certain principles are universally held. Second, Locke argues that there are no such universally held principles. He points to two principles that he think are the most likely candidates for universal assent:

I shall begin with the speculative, and instance in those magnified principles of demonstration, “Whatsoever is, is,” and “It is impossible for the same thing to be and not to be”; which, of all others, I think have the most allowed title to innate. These have so settled a reputation of maxims universally received, that it will no doubt be thought strange if any one should seem to question it. But yet I take liberty to say, that these propositions are so far from having an universal assent, that there are a great part of mankind to whom they are not so much as known.

Locke argues that even the law of identity and the law of non-contradiction are not universal held. He claims that “children and idiots have not the least apprehension or thought of them“. Certain people will then (on the innate view) have principles in their minds which never become knowledge. But if these principles are innate then they must become knowledge, says Locke. He puts it this way: “it seeming to me near a contradiction to say, that there are truths imprinted on the soul, which it perceives or understands not

Perhaps these innate notions are unlocked by the use of reason. Could this been an answer to the question of how there could be principles in the mind which are not perceived or become knowledge? Locke goes on to critique this possibility. First, he interprets the statement “that all men know and assent to them [the innate principles] when they come to the use of reason” in two ways:

1. That reason is used to discover these innate principles.

Locke argues, if I read him correctly, that this would imply that all knowledge gained from reasoning would then be innate. This would either contradict the innate view that only universally held knowledge(ie the law of identity) have innate principles or imply that knowledge gained by reasoning does not require the discovery of innate principles.

2. When reason is used these principles become apparent.

On this interpretation, Locke has two lines of critique. I will summarise one: When a person begins to reason from a young age they do not have immediate awareness of “It is impossible for the same thing to be and not to be“, which is one of the primary candidates for innate knowledge. Instead, people discover the law of non-contradiction by reasoning to it. If this is the case then Locke’s critique of interpretation one applies instead.

So there we have, in a nutshell, Locke’s arguments against innate knowledge. My next post will lay out Locke’s own view.

How could Locke’s arguments be strengthened? How could we strengthen the innate knowledge view Locke is critiquing?


1. John Locke article in the Stanford Encyclopedia of Philosophy

2. Practical principles are basically moral knowledge, while speculative principles refer to non-moral knowledge (eg Scientific or Theological). Speculative knowledge may, of course, have practical implications.