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Francis Bacon and the Four Idols of the Mind

Francis Bacon the Four Idols of the Mind

Among the Enlightenment founders, his spirit is the one that most endures.
It informs us across four centuries that we
must understand nature
both around us and within ourselves, in order to set humanity
on the course of self-improvement. 

-E.O. Wilson on Francis Bacon


The English statesman and scholar Francis Bacon (1561-1626) was one of the earliest thinkers to truly understand the nature of the mind and how humanity truly progresses in collective knowledge.

Bacon’s first great contribution was to lessen the focus on traditional scholarship: the constant mining of the old Greek and Roman philosophers and the old religious texts, the idea that most of our knowledge had already been “found” and needed to be rediscovered.

To Bacon, this was an unstable artifice on which to build our understanding of the world. Better that we start reasoning from first principles, building up our knowledge of the world through inductive reasoning. E.O. Wilson summarizes Bacon’s contribution in a chapter on the Enlightenment in his excellent book Consilience.

By reflecting on all possible methods of investigation available to his imagination, he concluded that the best among them is induction, which is the gathering of large numbers of facts and the detection of patterns. In order to obtain maximum objectivity, we must entertain only a minimum of preconceptions. Bacon proclaimed a pyramid of disciplines, with natural history forming the base, physics above and subsuming it, and metaphysics at the peak, explaining everything below–though perhaps in powers and forms beyond the grasp of man.

In this way, Wilson crowns Bacon as the Father of Induction — the first to truly grasp the power of careful inductive reasoning to generate insights. Bacon broke down the old, rigid ways of classifying knowledge in favor of building a new understanding from the ground up, using experiments to prove or disprove a theory.

In this way, he realized much of what was being taught in his time, including metaphysics, alchemy, magic, astrology, and other disciplines, would eventually crumble under scrutiny. (A feeling we share about our current age.)

Insights of the Mind

Most importantly, hundreds of years before the advent of modern psychology, Bacon understood clearly that the human mind doesn’t always reason correctly, and that any approach to scientific knowledge must start with that understanding. Over 400 years before there was a Charlie Munger or a Daniel Kahneman, Bacon clearly understood the first-conclusion bias and the confirmation bias.

In his Novum Organum, Bacon described these errors in the same manner we understand them today:

The mind, hastily and without choice, imbibes and treasures up the first notices of things, from whence all the rest proceed, errors must forever prevail, and remain uncorrected.


The human understanding when it has once adopted an opinion (either as being the received opinion or as being agreeable to itself) draws all things else to support and agree with it. And though there be a greater number and weight of instances to be found on the other side, yet these it either neglects and despises, or else by some distinction sets aside and rejects, in order that by this great and pernicious predetermination the authority of its former conclusions may remain inviolate.

He called the wide variety of errors in mental processing the Idols of the Mind. There were four idols: Idols of the Tribe, Idols of the Cave, Idols of the Marketplace, and Idols of the Theater.

Idols of the Tribe

The Idols of the Tribe made the false assumption that our most natural and basic sense of thing was the correct one. He called our natural impressions a “false mirror” which distorted the true nature of things.

The Idols of the Tribe have their foundation in human nature itself, and in the tribe or race of men. For it is a false assertion that the sense of man is the measure of things. On the contrary, all perceptions as well of the sense as of the mind are according to the measure of the individual and not according to the measure of the universe. And the human understanding is like a false mirror, which, receiving rays irregularly, distorts and discolors the nature of things by mingling its own nature with it.

Idols of the Cave

The Idols of the Cave were the problems of individuals, their passions and enthusiasms, their devotions and ideologies, all of which led to misunderstandings of the true nature of things.

The Idols of the Cave are the idols of the individual man. For everyone (besides the errors common to human nature in general) has a cave or den of his own, which refracts and discolors the light of nature, owing either to his own proper and peculiar nature; or to his education and conversation with others; or to the reading of books, and the authority of those whom he esteems and admires; or to the differences of impressions, accordingly as they take place in a mind preoccupied and predisposed or in a mind indifferent and settled; or the like. So that the spirit of man (according as it is meted out to different individuals) is in fact a thing variable and full of perturbation, and governed as it were by chance. Whence it was well observed by Heraclitus that men look for sciences in their own lesser worlds, and not in the greater or common world.

Idols of the Marketplace

You might call the Idols of the Marketplace a problem of political discourse: The use of words to mislead. (Nearly a half a century later, Garrett Hardin would argue similarly that good thinkers need a literary filter to suss out sense from nonsense.)

There are also Idols formed by the intercourse and association of men with each other, which I call Idols of the Market Place, on account of the commerce and consort of men there. For it is by discourse that men associate, and words are imposed according to the apprehension of the vulgar. And therefore the ill and unfit choice of words wonderfully obstructs the understanding. Nor do the definitions or explanations wherewith in some things learned men are wont to guard and defend themselves, by any means set the matter right. But words plainly force and overrule the understanding, and throw all into confusion, and lead men away into numberless empty controversies and idle fancies.

Idols of the Theater

The final idol, of the Theater, is how Bacon referred to long-received wisdom, the ancient systems of philosophy, the arbitrary divisions of knowledge and classification systems held onto like dogma. Without emptying one’s mind of the old ways, no new progress could be made. This would be an important lasting value of the Baconian view of science. Truth must be reasoned from first principles.

Lastly, there are Idols which have immigrated into men’s minds from the various dogmas of philosophies, and also from wrong laws of demonstration. These I call Idols of the Theater, because in my judgment all the received systems are but so many stage plays, representing worlds of their own creation after an unreal and scenic fashion. Nor is it only of the systems now in vogue, or only of the ancient sects and philosophies, that I speak; for many more plays of the same kind may yet be composed and in like artificial manner set forth; seeing that errors the most widely different have nevertheless causes for the most part alike. Neither again do I mean this only of entire systems, but also of many principles and axioms in science, which by tradition, credulity, and negligence have come to be received.

The Lasting Importance of Narrative

Even with his rationalistic view of the world, a rigorous devotion to truth, Bacon realized that unless you used creative storytelling and engaged a learner’s mind, it would be impossible to communicate real truths about the world. He knew the power narrative had to instruct. E.O. Wilson writes in Consilience:

Reality still had to be embraced directly and reported without flinching. But it is also best delivered the same way it was discovered, retaining a comparable vividness and play of the emotions. Nature and her secrets must be as stimulating to the imagination as are poetry and fables. To that end, Bacon advised us to use aphorisms, illustrations, stories, fables, analogies–anything that conveys truth from the discoverer to his readers as clearly as a picture. The mind, he argued, is not like a wax tablet. On a tablet you cannot write the new till you rub out the old, on the mind you cannot rub out the old except by writing in the new.”