Review: Knowledge Doesn't Exist and Other Thoughts on Critical Thinking

Knowledge Doesn't Exist and Other Thoughts on Critical Thinking #

By Christopher P. Dwyer Cambridge University Press, 2025

Dwyer, Christopher P. 2025. Knowledge Doesn't Exist and Other Thoughts on Critical Thinking. Cambridge: Cambridge University Press. ISBN 978-1-009-60273-0 (hardback), ISBN-13 9781009602730.

A book called Knowledge Doesn't Exist lands on the desk of a critical theorist carrying a promise its author never made. The title invites a misreading that matters for anyone in this field, so I begin with what the book is not. Dwyer's subject is critical thinking (hereafter CT), the psychology-of-cognition tradition that runs through the Delphi consensus, Facione, Halpern, King and Kitchener's reflective judgment, and Stanovich's work on rationality; it is not Critical Theory in the Frankfurt sense, and Dwyer knows the difference even if his cover does not advertise it. While the book delivers genuinely useful chapters on credibility, persuasion, and the honest limits of CT training, I will argue that its titular provocation amounts to repackaged Popper, that anecdote does the argumentative work its own framework forbids, and that its best use for critical theory is as a foil. Dwyer is a psychology researcher at the Technological University of the Shannon; the book succeeds his 2017 Cambridge volume Critical Thinking: Historical Perspectives and Practical Guidelines; and it grew directly out of his long-running Psychology Today blog, a genealogy he discusses openly in the introduction. That blog origin explains nearly everything about the book, its strengths included.

The framework, and where the book earns its keep #

Dwyer's model of CT is the field's mainstream one, presented clearly: skills (analysis, evaluation, inference) plus dispositions (the motivation to actually use them) plus reflective judgment (the epistemological understanding that knowledge claims vary in certainty) plus self-regulation, all riding on dual-process accounts of cognition. Where the book improves on most competitors is in its middle chapters on application. The chapter on evaluating information sources works through personal experience, common belief, research, expert opinion, and statistics as distinct credibility classes, and it is concrete enough to hand to a first-year doctoral student learning to weigh evidence. The chapter on changing minds is better still, because it takes seriously the finding that being right is not enough; it distinguishes audiences who have not thought critically from those who believe they have, and it treats rationalization as a question about who the arguer is really trying to convince. And the closing chapter's material on CT as expression, with its writing advice organized around argument structure, serves actual scholarly practice better than the abstract skill taxonomies that dominate the genre.

The book is also honest in places where the CT literature usually is not. Dwyer concedes that full-dress critical thinking is burdensome and rare, that people should reserve it for what they care about, and that the field faces a real problem in educators who teach CT without knowing the research. His late discussion of Stanovich's "mindware" openly flirts with contradiction, recommending heuristic-like knowledge structures as a practical substitute for the very reflective processing the book spends nine chapters advocating, and he names the tension himself rather than hiding it; he calls it fighting fire with fire. A footnote expressing skepticism that children can do CT at all, given the developmental demands of abstract reasoning, is the kind of unfashionable claim most textbook authors would cut.

The title is a humbug, and the argument under it is thinner than it sounds #

The titular chapter argues that knowledge, understood as certainly true belief, does not exist, because following Popper we can only falsify and never prove, so everything we hold is theory rather than truth. As epistemology this claim is both correct and old. Popper published Logik der Forschung in 1934, and the chapter's machinery (black swans, the null hypothesis, Pluto's reclassification, theory as the current best working model) is standard fare in any philosophy of science introduction. Dwyer anticipates the objection that his position amounts to radical skepticism and answers, "Please don't call it that. There's nothing radical about it." He is right, and that concession is the problem. A claim marketed by the book's own title as its provocative center turns out to be a consensus position in philosophy of science, stated without engagement with the philosophers who have complicated it. There is no Gettier, no contemporary epistemology, no reliabilism, no discussion of whether the colloquial concept of knowledge Dwyer demolishes is one any philosopher actually holds. The chapter succeeds as public pedagogy about the word "proof" and fails as an argument that could sustain a book title; the deflation, in short, is the reader's to perform, and the title does not survive it.

The deeper methodological problem shows in the same chapter's "Potential Criticisms" section, which is built around an anecdote. A colleague claims methodology should follow from epistemological standpoint; Dwyer disagrees, writes a piece about it, gets pushback from a qualitative researcher, and concludes that positivism, interpretivism, and the rest of the "-ists" are each fundamentally flawed, so he takes an appropriate collation of propositions from each. Readers from social theory will notice two things. First, the entire tradition of debate about epistemology and method, from the Methodenstreit through the positivism dispute in German sociology, is compressed into a story about a comment a colleague made. Second, the book's dismissal of standpoint epistemology is asserted rather than argued, at exactly the moment a reader trained in critical theory would want the argument; this lacuna sits precisely where the book's title had promised substance. A book that devotes a chapter to warning readers that anecdotal evidence is the weakest credibility class leans on anecdote as its argumentative engine here and throughout. Dwyer would likely answer that the conversational register is the point, that he is fighting fire with fire in the medium as well as the message. But there is a difference between accessible presentation of evidence and personal narrative doing the work evidence should do, and the book crosses that line regularly.

Structure and register #

The blog inheritance also shapes the book's architecture, mostly for the worse. Chapters proceed as loosely serialized essays with recurring "Concluding Thoughts" sections; ideas return in slightly different form across chapters; and the constant self-reference (my blog, my first book, my feedback, my mother's sayings) gives the whole a chatty, digressive rhythm that runs long. The informality is a deliberate choice, and Dwyer defends it as reaching readers academic prose cannot. Fair enough for the trade audience. For scholarly use the cost is precision, and occasionally the register produces claims stated with more swagger than support, as in the confident aside that if homeopathy worked, medicine would have monetized it by now, a cheerful argument from market efficiency that a critical theorist would enjoy taking apart.

For a critical theory doctoral seminar, the book's real value is as a foil, and I intend that as a genuine use, not a dismissal. It represents, in its best current form, the model of critique as an individual cognitive skill: trainable, testable, politically neutral, aimed at accuracy. Setting it against the Frankfurt tradition's model of critique as social theory, where the obstacles to clear thinking are structural and interested rather than merely cognitive, generates a productive confrontation. Dwyer's chapter on noisy information, conspiracy belief, and misinformation gestures toward the social, but its unit of analysis never stops being the individual thinker making better or worse moves. What produces the infodemic, who profits from it, and why bias is distributed the way it is are questions outside the book's frame; the two senses of "critical" are, in the end, not rivals but non-communicating registers, and the book never notices the other one exists.

Verdict #

Judged as what it is, an accessible, research-grounded guide to critical thinking for a general audience, this is a good book, better than most of its genre on sources, persuasion, and the honest limits of CT training. Judged by its title's promise of an epistemological intervention, it underdelivers, offering warmed-over Popper in place of engagement with the actual debates. And judged as a candidate text for critical theory, it is a category error, though a useful one to assign, precisely because working out why the two senses of "critical" diverge, and what each tradition cannot see about the other, is a genuinely instructive exercise. In my estimation, assign a chapter or two as counterpoint; read the whole thing only if you also want the blog.