“To maintain the state of doubt and to carry on systematic and protracted inquiry — these are the essentials of thinking.”
Decades before Carl Sagan published his now-legendary Baloney Detection Kit for critical thinking, the great philosopher, psychologist, and education reformer John Dewey penned the definitive treatise on the subject — a subject all the more urgently relevant today, in our age of snap judgments and instant opinions. In his 1910 masterwork How We Think (free download; public library), Dewey examines what separates thinking, a basic human faculty we take for granted, from thinking well, what it takes to train ourselves into mastering the art of thinking, and how we can channel our natural curiosity in a productive way when confronted with an overflow of information.
Dewey begins with the foundation of reflective thought, the defining quality of the fruitful, creative mind:
More of our waking life than we should care to admit, even to ourselves, is likely to be whiled away in this inconsequential trifling with idle fancy and unsubstantial hope…
Reflection involves not simply a sequence of ideas, but a consequence — a consecutive ordering in such a way that each determines the next as its proper outcome, while each in turn leans back on its predecessors. The successive portions of the reflective thought grow out of one another and support one another; they do not come and go in a medley. Each phase is a step from something to something — technically speaking, it is a term of thought. Each term leaves a deposit which is utilized in the next term. The stream or flow becomes a train, chain, or thread.
Thought, Dewey notes, also denotes belief, which he defines as “real or supposed knowledge going beyond what is directly present,” which is “marked by acceptance or rejection of something as reasonably probable or improbable.” But that process of acceptance or rejection is also where we brush up against one of the most quintessential human flaws, the same one responsible for the “backfire effect” — our tendency to construct our beliefs based on insufficient knowledge and understanding, then to cling to them blindly, rejecting all evidence to the opposite. Stereotypes and prejudice are among the products of such thinking. In that sense, our “thoughts” are not based on true reflection but on crippling cognitive shortcuts, often borrowed from society rather than arrived at by our own cerebration. Dewey writes:
Such thoughts grow up unconsciously and without reference to the attainment of correct belief. They are picked up — we know not how. From obscure sources and by unnoticed channels they insinuate themselves into acceptance and become unconsciously a part of our mental furniture. Tradition, instruction, imitation — all of which depend upon authority in some form, or appeal to our own advantage, or fall in with a strong passion — are responsible for them. Such thoughts are prejudices, that is, prejudgments, not judgments proper that rest upon a survey of evidence.
To truly think, Dewey argues, we ought to consider not only the origin of our beliefs but also how they affect our actions, which they inevitably do:
Thinking in its best sense is that which considers the basis and consequences of beliefs…
To think of the world as flat is to ascribe a quality to a real thing as its real property. This conclusion denotes a connection among things and hence is not, like imaginative thought, plastic to our mood. Belief in the world’s flatness commits him who holds it to thinking in certain specific ways of other objects, such as the heavenly bodies, antipodes, the possibility of navigation. It prescribes to him actions in accordance with his conception of these objects.
Dewey defines reflective thought, our single most potent antidote to erroneous beliefs:
Active, persistent, and careful consideration of any belief or supposed form of knowledge in the light of the grounds that support it, and the further conclusions to which it tends, constitutes reflective thought… It is a conscious and voluntary effort to establish belief upon a firm basis of reasons.
This basis of reasons, Dewey argues, is a relational framework for how different bits of knowledge connect to and validate one another. To think well is to construct fruitful linkages:
[The] function by which one thing signifies or indicates another, and thereby leads us to consider how far one may be regarded as warrant for belief in the other, [is] the central factor in all reflective or distinctively intellectual thinking… Reflection thus implies that something is believed in (or disbelieved in), not on its own direct account, but through something else which stands as witness, evidence, proof, voucher, warrant; that is, as ground of belief.
What follows naturally from this is the idea that to think is also to embrace uncertainty and harness the power of not-knowing:
Thinking … is defined accordingly as that operation in which present facts suggest other facts (or truths) in such a way as to induce belief in the latter upon the ground or warrant of the former. We do not put beliefs that rest simply on inference on the surest level of assurance. To say “I think so” implies that I do not as yet know so. The inferential belief may later be confirmed and come to stand as sure, but in itself it always has a certain element of supposition…
[There are] certain subprocesses which are involved in every reflective operation. These are: (a) a state of perplexity, hesitation, doubt; and (b) an act of search or investigation directed toward bringing to light further facts which serve to corroborate or to nullify the suggested belief.
Much like getting lost helps us find ourselves, being uncertain drives us to reflect, to seek knowledge. The spark of thinking, Dewey argues, is a kind of psychological restlessness rooted in ambiguity — what John Keats memorably termed “negative capability” — which precipitates our effort to resolve the unease by coming to, by way of reflection and deliberation, a conclusion:
Thinking begins in what may fairly enough be called a forked-road situation, a situation which is ambiguous, which presents a dilemma, which proposes alternatives. As long as our activity glides smoothly along from one thing to another, or as long as we permit our imagination to entertain fancies at pleasure, there is no call for reflection. Difficulty or obstruction in the way of reaching a belief brings us, however, to a pause. In the suspense of uncertainty, we metaphorically climb a tree; we try to find some standpoint from which we may survey additional facts and, getting a more commanding view of the situation, may decide how the facts stand related to one another…
Demand for the solution of a perplexity is the steadying and guiding factor in the entire process of reflection… This need of straightening out a perplexity also controls the kind of inquiry undertaken. A traveler whose end is the most beautiful path will look for other considerations and will test suggestions occurring to him on another principle than if he wishes to discover the way to a given city. The problem fixes the end of thought and the end controls the process of thinking.
This is where the art of critical thinking becomes crucial. Like the scientist, whose chief responsibility is always to remain uncertain, so the thinker must cultivate a capacity for not only welcoming but seeking out doubt:
If the suggestion that occurs is at once accepted, we have uncritical thinking, the minimum of reflection. To turn the thing over in mind, to reflect, means to hunt for additional evidence, for new data, that will develop the suggestion, and will either, as we say, bear it out or else make obvious its absurdity and irrelevance… The easiest way is to accept any suggestion that seems plausible and thereby bring to an end the condition of mental uneasiness. Reflective thinking is always more or less troublesome because it involves overcoming the inertia that inclines one to accept suggestions at their face value; it involves willingness to endure a condition of mental unrest and disturbance. Reflective thinking, in short, means judgment suspended during further inquiry; and suspense is likely to be somewhat painful… To maintain the state of doubt and to carry on systematic and protracted inquiry — these are the essentials of thinking.
Just as importantly, Dewey argues, reflective thought acts as an antidote to autopilot — it “affords the sole method of escape from purely impulsive or purely routine action.” But like the use of any tool, thinking “may go wrong as well as right, and hence … needs safeguarding and training.” Dewey admonishes against the assumption that one’s intelligence prevents the operation from going wrong — if anything, the relationship between creativity and dishonesty suggests that the most intelligent people are often those most deft at rationalizing their erroneous beliefs and the resulting behaviors. Dewey writes:
Natural intelligence is no barrier to the propagation of error, nor large but untrained experience to the accumulation of fixed false beliefs. Errors may support one another mutually and weave an ever larger and firmer fabric of misconception.
Perhaps the greatest gift of thought, Dewey notes, is that it allows us to imagine things not yet experienced, based on what we know in and about the present — it grants us the power of “systematized foresight,” which enables us to “act on the basis of the absent and the future.” And yet therein lies one of the most perilous potential pitfalls, as well as the greatest potentiality of learning the art of reflective thought:
The process of reaching the absent from the present is peculiarly exposed to error; it is liable to be influenced by almost any number of unseen and unconsidered causes — past experience, received dogmas, the stirring of self-interest, the arousing of passion, sheer mental laziness, a social environment steeped in biased traditions or animated by false expectations, and so on. The exercise of thought is, in the literal sense of that word, inference; by it one thing carries us over to the idea of, and belief in, another thing. It involves a jump, a leap, a going beyond what is surely known to something else accepted on its warrant. Unless one is an idiot, one simply cannot help having all things and events suggest other things not actually present, nor can one help a tendency to believe in the latter on the basis of the former. The very inevitableness of the jump, the leap, to something unknown, only emphasizes the necessity of attention to the conditions under which it occurs so that the danger of a false step may be lessened and the probability of a right landing increased.
Paying attention, essentially, means understanding the context in which an idea occurs and the conditions under which it is given credence — in other words, knowing why we believe what we believe. That, Dewey argues, is a function of critical thinking, the result of which is proof — something without which we can’t be certain that what we believe is true:
To prove a thing means primarily to try, to test it… Not until a thing has been tried — “tried out,” in colloquial language — do we know its true worth. Till then it may be pretense, a bluff. But the thing that has come out victorious in a test or trial of strength carries its credentials with it; it is approved, because it has been proved.
(How brilliantly this applies not only to the pursuit of capital-T truth, but also to the basic fabric of our wants and desires — so often we dismiss something as unworthy without having tried it out. To dismiss experiences and ideas in that way is, then, a profound failure of reflective thinking and of our highest human potentiality.)
In testing our inferences, Dewey argues, it’s crucial to discriminate between “beliefs that rest upon tested evidence and those that do not” and to be mindful of “the kind and degree of assent yielded,” both of which require a rich library of knowledge and experience against which to test our beliefs.
This notion strikes with particular resonance: I founded Brain Pickings around the concept of combinatorial creativity, the idea that our capacity to create — which is, essentially, a function of fruitful thinking — is predicated on a vast and diverse pool of insights, impressions, influences, and other mental resources.
Dewey captures this elegantly in considering “the factors essential to thought”:
Thinking involves … the suggestion of a conclusion for acceptance, and also search or inquiry to test the value of the suggestion before finally accepting it. This implies (a) a certain fund or store of experiences and facts from which suggestions proceed; (b) promptness, flexibility, and fertility of suggestions; and (c) orderliness, consecutiveness, appropriateness in what is suggested. Clearly, a person may be hampered in any of these three regards: His thinking may be irrelevant, narrow, or crude because he has not enough actual material upon which to base conclusions; or because concrete facts and raw material, even if extensive and bulky, fail to evoke suggestions easily and richly; or finally, because, even when these two conditions are fulfilled, the ideas suggested are incoherent and fantastic, rather than pertinent and consistent.
We stock our “store of experiences and facts” via one of the greatest human faculties — our inherent curiosity, a “desire for the fullness of experience”:
The most vital and significant factor in supplying the primary material whence suggestion may issue is, without doubt, curiosity… The curious mind is constantly alert and exploring, seeking material for thought, as a vigorous and healthy body is on the qui vive for nutriment. Eagerness for experience, for new and varied contacts, is found where wonder is found. Such curiosity is the only sure guarantee of the acquisition of the primary facts upon which inference must base itself.
Dewey explores curiosity at its most natural and uncontaminated — in the child’s mind. Children not only offer a model for fruitful risk-taking and overcoming the fear of failure, but their boundless curiosity, he argues, is precisely what we need to reawaken in ourselves in seeking to cultivate fertile thought:
In its first manifestations, curiosity is a vital overflow, an expression of an abundant organic energy. A physiological uneasiness leads a child to be “into everything” — to be reaching, poking, pounding, prying… The most casual notice of the activities of a young child reveals a ceaseless display of exploring and testing activity. Objects are sucked, fingered, and thumped; drawn and pushed, handled and thrown; in short, experimented with, till they cease to yield new qualities. Such activities are hardly intellectual, and yet without them intellectual activity would be feeble and intermittent through lack of stuff for its operations.
From this springs the next developmental stage, the what/why phase that often exasperates parents and teachers but provides the foundation for critical thinking:
A higher stage of curiosity develops under the influence of social stimuli. When the child learns that he can appeal to others to eke out his store of experiences, so that, if objects fail to respond interestingly to his experiments, he may call upon persons to provide interesting material, a new epoch sets in. “What is that?” “Why?” become the unfailing signs of a child’s presence… Yet there is more than a desire to accumulate just information or heap up disconnected items, although sometimes the interrogating habit threatens to degenerate into a mere disease of language. In the feeling, however dim, that the facts which directly meet the senses are not the whole story, that there is more behind them and more to come from them, lies the germ of intellectual curiosity.
Curiosity rises above the organic and the social planes and becomes intellectual in the degree in which it is transformed into interest in problems provoked by the observation of things and the accumulation of material. When the question is not discharged by being asked of another, when the child continues to entertain it in his own mind and to be alert for whatever will help answer it, curiosity has become a positive intellectual force. To the open mind, nature and social experience are full of varied and subtle challenges to look further.
Once again, Dewey reminds us that this unique human gift is predicated on our fragile willingness to befriend uncertainty and welcome the unknown — something most of us relinquish by mid-life. Lamenting the ease with which “the open-minded and flexible wonder of childhood” is lost, Dewey writes:
If germinating powers are not used and cultivated at the right moment, they tend to be transitory, to die out, or to wane in intensity. This general law is peculiarly true of sensitiveness to what is uncertain and questionable; in a few people, intellectual curiosity is so insatiable that nothing will discourage it, but in most its edge is easily dulled and blunted.
In a sidebar comment on the notion of dullness, he considers the very metaphors we use for the quality of the mind in a rather lyrical passage:
The common classification of persons into the dull and the bright is made primarily on the basis of the readiness or facility with which suggestions follow upon the presentation of objects and upon the happening of events. As the metaphor of dull and bright implies, some minds are impervious, or else they absorb passively. Everything presented is lost in a drab monotony that gives nothing back. But others reflect, or give back in varied lights, all that strikes upon them. The dull make no response; the bright flash back the fact with a changed quality.
But Dewey’s most prescient point has to do with how information overload — a malady undoubtedly far worse today than it was in 1910, yet one each era bemoans by its own terms — muddles the clarity of our view, hindering our ability to think critically and reflectively:
So many suggestions may rise that the person is at a loss to select among them. He finds it difficult to reach any definite conclusion and wanders more or less helplessly among them… There is such a thing as too much thinking, as when action is paralyzed by the multiplicity of views suggested by a situation… The very number of suggestions may be hostile to tracing logical sequences among them, for it may tempt the mind away from the necessary but trying task of search for real connections, into the more congenial occupation of embroidering upon the given facts a tissue of agreeable fancies. The best mental habit involves a balance between paucity and redundancy of suggestions.
In today’s culture of exponentially growing “multiplicity of views,” Dewey’s admonition exposes with great urgency both meanings of critical in “critical thinking.” (Thirty-five years later, in 1945, Vannevar Bush would propose a complementary solution to the predicament by predicting the emergence of “a new profession of trail blazers” — essentially, knowledge sherpas who “find delight in the task of establishing useful trails through the enormous mass of the common record.”)
For Dewey, the solution was in large part a matter of depth — how deep we are willing to penetrate the bottomless pit of information. It is our capacity for depth that determines the richness and fruitfulness of our thought — something of equally urgent importance today, when the information web is dominated by bite-sized opinion riffs and “How Cat Are You?” quizzes. Deep-diving, according to Dewey, is something that can and should be taught:
One man’s thought is profound while another’s is superficial; one goes to the roots of the matter, and another touches lightly its most external aspects. This phase of thinking is perhaps the most untaught of all, and the least amenable to external influence whether for improvement or harm. Nevertheless, the conditions of the [person's] contact with subject-matter may be such that he is compelled to come to quarters with its more significant features, or such that he is encouraged to deal with it upon the basis of what is trivial. The common assumptions that, if the [person] only thinks, one thought is just as good for his mental discipline as another, and that the end of study is the amassing of information, both tend to foster superficial, at the expense of significant, thought.
Even more important, in our era of snap-judgments and instant opinions, is Dewey’s point about the slowness and deliberative contemplation inherent to such deep thought:
Sometimes slowness and depth of response are intimately connected. Time is required in order to digest impressions, and translate them into substantial ideas. “Brightness” may be but a flash in the pan. The “slow but sure” person … is one in whom impressions sink and accumulate, so that thinking is done at a deeper level of value than with a slighter load… The depth to which a sense of the problem, of the difficulty, sinks, determines the quality of the thinking that follows.
Ultimately, Dewey argues that thinking is predicated on mapping out the interaction of information and on an intentional organization of knowledge — something that requires a comfort with uncertainty, a systematic curiosity that stocks the mental store of ideas, and a willingness for depth and slowness:
Thinking [is] not a machine-like, ready-made apparatus to be turned indifferently and at will upon all subjects, as a lantern may throw its light as it happens upon horses, streets, gardens, trees, or river. Thinking is specific, in that different things suggest their own appropriate meanings, tell their own unique stories, and in that they do this in very different ways with different persons. As the growth of the body is through the assimilation of food, so the growth of mind is through the logical organization of subject-matter. Thinking is not like a sausage machine which reduces all materials indifferently to one marketable commodity, but is a power of following up and linking together the specific suggestions that specific things arouse.
Facts, whether narrow or extensive, and conclusions suggested by them, whether many or few, do not constitute, even when combined, reflective thought. The suggestions must be organized; they must be arranged with reference to one another and with reference to the facts on which they depend for proof. When the factors of facility, of fertility, and of depth are properly balanced or proportioned, we get as the outcome continuity of thought. We desire neither the slow mind nor yet the hasty. We wish neither random diffuseness nor fixed rigidity. Consecutiveness means flexibility and variety of materials, conjoined with singleness and definiteness of direction.
And yet, he is careful to point out, it is not a black-and-white matter of tuning out distraction and pursuing absolute concentration — that, in fact, is the very mechanism by which we confine ourselves to our existing beliefs, never leaving our comfort zone of knowledge and opinion. Good thinking, he argues, embraces contradiction rather than shunning it:
Concentration does not mean fixity, nor a cramped arrest or paralysis of the flow of suggestion. It means variety and change of ideas combined into a single steady trend moving toward a unified conclusion. Thoughts are concentrated not by being kept still and quiescent, but by being kept moving toward an object, as a general concentrates his troops for attack or defense. Holding the mind to a subject is like holding a ship to its course; it implies constant change of place combined with unity of direction. Consistent and orderly thinking is precisely such a change of subject-matter. Consistency is no more the mere absence of contradiction than concentration is the mere absence of diversion — which exists in dull routine or in a person “fast asleep.” All kinds of varied and incompatible suggestions may sprout and be followed in their growth, and yet thinking be consistent and orderly, provided each one of the suggestions is viewed in relation to the main topic.
So why would we ever go through all that trouble in the first place, rather than sinking into our comfortable routine? Dewey argues that thinking arises from the need to action — something undoubtedly evidenced by the history of successful entrepreneurship, wherein many great inventions came from the inventor’s own need for something that didn’t yet exist in the world, be it the Polaroid camera, which Edwin Land dreamed up after his little daughter asked why she couldn’t see a photograph right after it was taken, or Instapaper, which Marco Arment built out of frustration with how hard it was to read web articles on the iPhone offline. Dewey writes:
Intellectual organization originates and for a time grows as an accompaniment of the organization of the acts required to realize an end, not as the result of a direct appeal to thinking power. The need of thinking to accomplish something beyond thinking is more potent than thinking for its own sake. All people at the outset, and the majority of people probably all their lives, attain ordering of thought through ordering of action.
How We Think is a magnificent read in its entirety, exploring everything from the defects and potential reform of the education system to how we can train ourselves to interpret facts and create meaning out of them. It is available as a free ebook.
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