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John Locke on Knowledge, Understanding, and Why Not to Borrow Your Opinions from Others

John Locke on Knowledge, Understanding, and Why Not to Borrow Your Opinions from Others

English philosopher and physician John Locke (August 29, 1632–October 28, 1704), endures as one of the most influential figures of the Enlightenment, whose work shaped the course of modern thought, permeated the American Declaration of Independence, and laid the foundation for today’s understanding of the self and human identity. One of his most central tenets was the idea, radical at the time, that we are born without innate ideas and that knowledge instead is acquired through direct experience and sense perception. That’s precisely what Locke explores in his seminal 1690 masterwork An Essay Concerning Human Understanding (public library | free ebook), often considered the catalyst for contemporary Western conceptions of the self — a dimensional inquiry into “the [origin], certainty, and extent of human knowledge, together with the grounds and degrees of belief, opinion, and assent.”


Locke writes:

Every step the mind takes in its progress towards Knowledge makes some discovery, which is not only new, but the best too, for the time at least.

For the understanding, like the eye, judging of objects only by its own sight, cannot but be pleased with what it discovers, having less regret for what has escaped it, because it is unknown. Thus he who has raised himself above the alms-basket, and, not content to live lazily on scraps of begged opinions, sets his own thoughts on work, to find and follow truth, will (whatever he lights on) not miss the hunter’s satisfaction; every moment of his pursuit will reward his pains with some delight; and he will have reason to think his time not ill spent, even when he cannot much boast of any great acquisition.

Like Thoreau, who nearly two centuries later similarly admonished against adopting the thoughts of others without critical thinking, Locke is especially dismissive of such borrowed opinions:

It is not worth while to be concerned what he says or thinks, who says or thinks only as he is directed by another.

He argues that since our capacity for understanding is what makes us human, it is our duty to explore how our understanding works — but these processes, not unlike attention, operate beneath the threshold of our awareness and thus require deliberate effort:

The understanding, like the eye, whilst it makes us see and perceive all other things, takes no notice of itself; and it requires an art and pains to set it at a distance and make it its own object. But whatever be the difficulties that lie in the way of this inquiry; whatever it be that keeps us so much in the dark to ourselves; sure I am that all the light we can let in upon our minds, all the acquaintance we can make with our own understandings, will not only be very pleasant, but bring us great advantage, in directing our thoughts in the search of other things.

Equally, Locke argues, we need to direct our awareness to how our “knowledge” — what we’ve come to believe and embraced as conviction — comes to be:

I can give any account of the ways whereby our understandings come to attain those notions of things we have; and can set down any measures of the certainty of our knowledge; or the grounds of those persuasions which are to be found amongst men, so various, different, and wholly contradictory; and yet asserted somewhere or other with such assurance and confidence, that he that shall take a view of the opinions of mankind, observe their opposition, and at the same time consider the fondness and devotion wherewith they are embraced, the resolution and eagerness wherewith they are maintained, may perhaps have reason to suspect, that either there is no such thing as truth at all, or that mankind hath no sufficient means to attain a certain knowledge of it. … It is therefore worth while to search out the bounds between opinion and knowledge; and examine by what measures, in things whereof we have no certain knowledge, we ought to regulate our assent and moderate our persuasion.

Ultimately, Locke maintains that all ideas coalesce from the confluence of sensation and deliberate thought — an early conception of later models for how creativity works:

All Ideas come from Sensation or Reflection. Let us then suppose the mind to be, as we say, white paper, void of all characters, without any ideas: — How comes it to be furnished? Whence comes it by that vast store which the busy and boundless fancy of man has painted on it with an almost endless variety? Whence has it all the materials of reason and knowledge? To this I answer, in one word, from experience. In that all our knowledge is founded; and from that it ultimately derives itself. Our observation employed either, about external sensible objects, or about the internal operations of our minds perceived and reflected on by ourselves, is that which supplies our understandings with all the materials of thinking. These two are the fountains of knowledge, from whence all the ideas we have, or can naturally have, do spring.


External objects furnish the mind with the ideas of sensible qualities, which are all those different perceptions they produce in us; and the mind furnishes the understanding with ideas of its own operations.

An Essay Concerning Human Understanding, very much worth a read in its entirety, is in the public domain and is thus available as a free download.

Published August 29, 2013




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