Published in 1689 though formally dated 1690, John Locke’s An Essay Concerning Human Understanding is one of the most important works of Enlightenment philosophy: indeed, in many ways, Locke paved the way for the (later) Enlightenment.
But what is it about An Essay Concerning Human Understanding, and Locke’s argument, which makes him so important?
You can read the whole of An Essay Concerning Human Understanding here (the text is taken from the original 1689 edition, which erroneously gave the title as An Essay Concerning Humane Understanding), but we’ve tried to summarise the main points of Locke’s argument below, before proceeding to an analysis of his meaning – and his significance.
An Essay Concerning Human Understanding: summary
Locke begins the Essay by arguing against the earlier rationalist idea (propounded by Descartes among others) that ideas can be innate within the human mind. For Locke, when babies are born their minds are empty: a notion which he famously calls the tabula rasa (literally, ‘blank slate’). Human minds are like a blank sheet of paper when we’re born, and everything that ends up in them is supplied by experience.
This signals Locke’s adherence to empiricism over rationalism: rather than believing knowledge and ideas about the world are in-built within us by nature, he believes that ideas are acquired from external stimuli, from us going out there into the world and being exposed to things.
Book II develops this idea in more detail. Experience is the bedrock of all human knowledge. We don’t inherently ‘know’ things: we learn about things as we experience them. This is a bit like a ‘nurture over nature’ view. There are two routes to knowledge via experience: sensation and reflection. Sensation is about coming into contact with the external world, whereas reflection comes from introspection, or from reflecting on what we have experienced.
Book III proposes an idea later developed in more depth by Immanuel Kant: that we cannot ever know true reality, only our perception of it. And our perception of reality is necessarily subjective: you don’t have precisely the same experience of the world as I do. It is also in Book III that Locke attempts to apply his empiricist approach to language.
Book IV appears, on the face of it, to contradict what Locke had set out to argue: namely, that empiricism rather than rationalism is the correct way to view knowledge. But he is actually arguing that, once we adopt an empirical mindset, we are then able to draw a rationalist conclusion of the world from that experience.
An Essay Concerning Human Understanding: analysis
The twentieth-century philosopher Isaiah Berlin once suggested that John Locke effectively invented the idea of common sense in matters of philosophy, and An Essay Concerning Human Understanding is certainly a powerful defence of the importance of an empiricist outlook, whereby we trust our own senses and experiences rather than simply assuming things to be innately true and unquestionable. Bertrand Russell made a similar claim about Locke’s book.
What this means is that Locke’s contribution to philosophy lies partly in his emphasis on the importance of experience in forming our ideas and values. Empiricism places the emphasis on our own sensory understanding of the world (what is now sometimes called ‘lived experience’, to offer a broader term).
This means that we trust our own senses rather than some innate knowledge we come pre-programmed with at birth. How do we know right from wrong? Locke would argue that we have to learn what ‘right’ and ‘wrong’ mean in order to know that.
Locke is, of course, right to emphasise the importance of experience in forming our knowledge of the world. But, in his determination to oppose the rationalist approach touted by Spinoza, Descartes, and others, does he take things too far in the other direction?
There are many moral philosophers who would argue that we do have an innate sense of right and wrong which is present at birth, even if we’re too young to act on it as soon as we leave the womb. Evolutionary biologists would argue that we wouldn’t have got as far as we have as a species without this in-built sense of morality, among other things.
There are other aspects of An Essay Concerning Human Understanding which critics have argued are too reductive. Although our own experience is obviously important in shaping our view of the world, few would go so far as Locke and argue that it’s the only significant factor.
For one thing, our experience of the world is just too different: a man living in a secluded monastery in Yorkshire is unlikely to arrive at the same ‘knowledge’ of the world as a midwife working in London. Locke grants that our experiences will necessarily be subjective, but where does that leave us when considering supposedly self-evident or universal truths, such as ‘killing is wrong’ or ‘do unto others as you would have them to do you’?
Nevertheless, An Essay Concerning Human Understanding is an important book, not least because it was a milestone in philosophy and would act as the foundation for the work of many philosophers who came after Locke.