Susan Haack — An Introductory Guide

Compiled by Ralph Dumain

Note: As I recall, I attended a talk by Susan Haack on “The Justification of Deduction” at the Buffalo Logic Colloquium in 1980. I subsequently read her book Deviant Logic. The work on logic reflected her focus in the early part of her career, which since mushroomed in scope and output. Recently, I found my way back to her work, via two themes that vitally interest me: (1) the flawed ideology of scientism (and its complement, anti-science and irrationalism, both in philosophy and the atheist movement; (2) the triviality, faddishness, and corruption of academic philosophy in the Anglo-American (particularly American) sphere. Haack opposes both scientism (including the trend towards reduction of philosophy to science) and irrationalism (including Richard Rorty and feminist epistemology). Her technical interventions are just as interesting.

Haack’s works listed below, together with my commentary, reflect my ongoing engagement with her writings, and this selective guide will expand accordingly. I have surveyed some of her essays on logic. I have not yet engaged her work on epistemology and philosophy of science or on law. All in all, I find her take on the subjects I have examined to be refreshingly different from the general run of analytical philosophy. Haack is not a camp-follower or a narrow pedant. Within the world she inhabits, interfacing with analytical philosophy and philosophy of science, I find her perspective and her work invaluable. I do not think that her quest to reintegrate philosophy encompasses everything I think it needs to from the broadest and deepest possible perspective, but within its world, it is indispensable, and must be taken into account in reconstructing the big picture out of the fragments bequeathed to the world.

Most of her papers, essays, interviews, and dozens of other works (including translations, Power Point presentations, et al) not listed here can be located via her web page at Note that one must continually scroll down to access more items on this page. Also, she continually adds more material. (21 April 2018)

Basic access points:

Susan Haack - Wikipedia, the free encyclopedia

Susan Haack’s Web Page at University of Miami

Susan Haack at

The monograph to read:

Scientism and its Discontents (2017) by Susan Haack

This freely downloadable book is based on Haack’s September 2016 Agnes Cuming Lectures at University College, Dublin.

Inter alia, this is the single most important source for combating the intellectual and ideological backwardness of the atheist / humanist / skeptics movement. Haack opposes irrationalism (not only religious anti-science, but also postmodernism, subjectivist sociology of science, and feminist philosophy of science), but she also opposes the insufferable childishness and intellectual charlatanism (my words) of scientism that abounds in—nay dominates—the contemporary (American/British) atheist/etc. movement. Critiques of scientism are readily available, but a detailed anatomy of what is wrong with scientism is not so readily had, and this is your one-stop source.

Haack targets the contemporary propaganda dismissing philosophy and other humanities, now tied to the surge and abuse of evolutionary psychology and neuroscience. Haack notes that “scientistic philosophy is on the rise just as the integrity of science itself is under threat, and for some of the same reasons.” Haack delineates the evolution of the concept of science and its narrowing to its dominant contemporary usage in the English language. She also argues for the continuity of “science” with disciplined research and reasoning outside of “science” proper, and what science in the modern sense has added to this. She also deflates the notion of a unitary scientific method and a neat typology of sciences.

She argues that the notion of “pseudo-science” is itself pseudo-scientific, though for legal as well as other reasons it is necessary to distinguish the real thing from the bogus. She also emphasizes that much junk science has infiltrated respectable science due to methodological shoddiness, the imperatives of careerism, ideological bias, or external corrupting influences. Concomitant with this, she rejects the demarcation problem as a viable endeavor. And importantly, Haack eviscerates Karl Popper’s philosophy of science, of which scientists themselves understand—vaguely at best—only the falsifiability criterion. She dismisses Popper’s attempt to isolate Freud’s and Marx’s theories as non-scientific, not herself defending these endeavors.

Furthermore, she legitimates other cognitive activities outside of science, and argues that while science will advance in certain areas, it will never explain everything or advance to the point where it will subsume extra-scientific judgment.

Haack itemizes and explains the telltale signs of scientism. All this is in the first lecture of the two.

On the fragmentation & reintegration of philosophy

The Fragmentation of Philosophy, the Road to Reintegration,” in Susan Haack: Reintegrating Philosophy, edited by Julia F. Göhner and Eva-Maria Jung (Heidelberg: Springer, 2016), pp. 3-32. (Münster Lectures in Philosophy; Volume 2) Links are to Haack’s individual essay. Also at Filosofia - UFRGS.

“Now I begin to see that there’s a kind of vicious spiral here: when specialization is premature, it wastes time and energy because there is as yet nothing like the body of well-warranted theory needed to make it productive. When premature specialization becomes commonplace, the prospects for achieving something solid to build on seem to recede indefinitely; and so people keep themselves busy arguing over and over the same puzzles—until boredom sets in, and they set off in pursuit of a new fad.” [p. 21]

“If the current fragmentation of philosophy is as intellectually disastrous as I have claimed, then there can’t be intellectually respectable reasons for the disintegration of our discipline into petty fiefdoms; in particular, the explanation can’t be that people realize that this or that important discovery has brought solutions to these and those more specific problems within reach, and so focus on solving them. In short, the explanation can’t be intellectual opportunity—philosophers’ fastening on promising ways to contribute to the growth of knowledge; it must be at least in part a matter of academic opportunism—philosophy professors’ fastening on promising ways to advance their careers.” [p. 24]

Formal Philosophy: A Plea for Pluralism” (2005)

The question initially is: what role does formal logic have in philosophical inquiry, and what are its limitations, especially in addressing the big questions. She began as a student with linguistic philosophy in England, and launched into a study of logic, about which she has many interesting things to say. (Her essay begins with quotes from Frege and Nietzsche.) She describes her entire philosophical trajectory, expanding into her view on epistemology, questioning the limitations of the neopositivists and neopragmatists, and finally reluctantly listing her big questions for philosophy’s future after listing Peirce’s. Peirce is her guiding light on the pursuit of serious philosophy. She is a Britisher who sometimes labels herself an American philosopher. I found her remarks about logic especially interesting.

Meaning Grows, and It’s a Good Thing, Too,” The Philosophers’ Magazine, issue 50, 3rd quarter 2010: The Best Ideas of the 21st Century. One essay on the alleged 50 best ideas.

Haack is skeptical both of the existence of 50 new ideas and of the obsession with novelty. For her, conceptual innovation involves growth of meaning, as developed in her book Defending Science Within Reason (2003). “The meanings of scientific terms evolve as science advances,” which helps rather than hinders scientific progress. Purely formal models of science (deductivist, inductivist, probablistic) are erroneous. She applies this reasoning also to legal theory. Philosophical concepts also have a history. She distinguishes between productive and counter-productive meaning-change. Peirce already suggested that “meaning grows,” an idea neglected by ahistorical analytic philosophy.

Scientism & the corruption of academia

The Future of Philosophy, the Seduction of Scientism”. Also at

This is excerpted and adapted from the volume Scientism and Its Discontents (2017).

The Real Question: Can Philosophy Be Saved?Free Inquiry 37, no.6, October 2017, pp. 40-43. (University of Miami Legal Studies Research Paper No. 17-31)

This is an essential part of the big picture of what has gone wrong and what has to be incorporated into the larger picture not discussed, i.e. the map of philosophy outside the USA and beyond the Anglophone sphere. It is also relevant to the scientism prevalent in the atheist / humanist / skeptics movement.

Six Signs of Scientism,” Logos & Episteme, vol. 3, no. 1, 2012, pp. 75-95.

The six signs are:

1. Using the words “science,” “scientific,” “scientifically,” “scientist,” etc., honorifically, as generic terms of epistemic praise.
2. Adopting the manners, the trappings, the technical terminology, etc., of the sciences, irrespective of their real usefulness.
3. A preoccupation with demarcation, i.e., with drawing a sharp line between genuine science, the real thing, and “pseudo-scientific” imposters.
4. A corresponding preoccupation with identifying the “scientific method,” presumed to explain how the sciences have been so successful.
5. Looking to the sciences for answers to questions beyond their scope.
6. Denying or denigrating the legitimacy or the worth of other kinds of inquiry besides the scientific, or the value of human activities other than inquiry, such as poetry or art.

Haack proceeds to detail each of these. Under trappings, note the imitation of scientific citation styles, the inappropriate tendency to cite only the most recent literature, the stacked deck of peer review, unnecessary jargon-ladenness. Under demarcation, she singles out Popper, both his general approach and his specific inept handling of Marxism as non-scientific. The demarcation criterion obscures the continuity of “scientific” and ostensibly extra-scientific inquiry and obscures the presence of junk science within “science.” Under the reduction of ethical and other philosophical questions to scientific ones (5), Haack singles out E. O. Wilson’s “evolutionary ethics.”

Haack also outlines the history of the term “scientism” and its transition to a negative designation, noting that it is now used positively most conspicuously by Michael Shermer.

Preposterism and Its Consequences,” in Manifesto of a Passionate Moderate: Unfashionable Essays (Chicago; London: The University of Chicago Press, 1998), pp. 188-208.

On scientism, anti-science, and sham reasoning in philosophy:

“Perhaps that is why the revolutionary scientism encountered in contemporary philosophy often manifests a peculiar affinity with the antiscientific attitudes which, as I conjecture, are prompted by resentment, as scientism is prompted by envy, of the sciences.” Paul Churchland, on the scientistic side, tells us that, since truth is not the primary aim of the ceaseless cognitive activity of the ganglia of the sea slug, it should maybe cease to be a primary aim of science, and even that talk of truth may make no sense; Richard Rorty, on the antiscience side, tells us that truth is just what can survive all conversational objections, and that the only sense in which science is exemplary is as a model of human solidarity. Patricia Churchland, on the scientistic side, observes that “truth, whatever that is, definitely takes the hindmost”; Sandra Harding, on the antiscience side, observes that “the truth—whatever that is!—will not set you free.” Stephen Stich, on the scientistic side, announces that truth is neither intrinsically nor instrumentally valuable, and that a justified belief is one his holding which conduces to whatever the believer values; Steve Fuller, on the antiscience side, announces that he sees no distinction “between ‘good scholarship’ and ‘political relevance.’”

Science, Scientism, and Anti-Science in the Age of Preposterism,” Skeptical Inquirer, Volume 21, no. 6, November / December 1997.

Here Haack decries the corruption of standards in academia, particularly in philosophy. She sees it being corrupted by business imperatives and the interdependent dynamic of scientism and anti-scientism. An example of the former is the lucrative area of cognitive science, eclipsing epistemology. As for anti-science, she roundly condemns, as she should, feminist philosophy, which she regards as a sham. “Now one begins to see why the revolutionary scientism encountered in contemporary philosophy often manifests a peculiar affinity with the anti-scientific attitudes which, as I conjecture, are prompted by resentment, as scientism is prompted by envy, of the sciences. Both parties have become disillusioned with the very idea of honest inquiry, of truth-seeking.”

More on the atheist / freethought / humanist / skeptical movement:

Interview with Susan Haack by Richard Carrier, Freethought Blogs, May 6, 2012

This interview mostly concerns Haack’s personal and philosophical history and perspectives, with only a few remarks on atheism and the atheist movement..

More on philosophy & intellectual life:

Serious Philosophy” (2016) or “Serious Philosophy: A Peircean Perspective” (2018)

From the abstract: “Calling on ideas from C.S. Peirce, Haack argues first that philosophy is a serious form of inquiry, requiring real commitment and real intellectual effort, and then that playfulness and humor may actually be of help in such inquiry, while solemnity and self-importance will, for sure, impede it.”

The Ideal of Intellectual Integrity, in Life and Literature,” New Literary History, vol. 36, no. 3, Summer 2005, pp. 359-373.

Haack draws on advocacy of intellectual integrity from literary works, philosophy, and science. She quotes Hitler on opposition to the very concept. She disavows contemporary cynicism regarding the concept and value of truth. We live in a misinformation-saturated environment, and academic provides no better role model for intellectual integrity.

The “two cultures”

[Contribution to] The Rise and Fall of a Cultural Legend, New Scientist, 2 May 2009; introduction by Stephen Collini, p. 26. Susan Haack, Harry Collins, Mary Midgley, Sandra Harding, A. C. Grayling, p. 27.

This is a short piece on the legacy of C. P. Snow’s 1959 essay, “The Two Cultures.” Haack contributes two short paragraphs: Snow oversimplifies even with his caveat that he should not. Haack: “For intellectual life is both more and less integrated than Snow acknowledges”: specialization has issued in a plurality of subcultures. At the other end, the respect for evidence—the “moral component”—is a shared value of many scientists and humanists.

More on analytical philosophy:

Carnap’s ‘Aufbau’: Some Reflections,” Ratio, vol. 19, no, 2, December 1977, pp. 170-175.

Carnap was inspired by Frege and Russell. If mathematics could be reduced to logic, then, according to Russell’s phenomenalism, “physical objects could be reduced to logical constructions out of sense-data.” While Carnap acknowledges that he studied Kant, few references to Kant can be found in his work. Haack proposes that, whether conscious of it or not, notable similarities can be found between the Aufbau and Kant’s Critique of Pure Reason. She addresses Carnap’s “‘rational reconstruction’ of empirical knowledge,” with its “constraint of epistemic priority” that “requires the choice of a phenomenal basis.” She finds that “Carnap’s programme is logical rather than psychological; but the introduction of the constraint of epistemic priority brings in an inescapably psychological element.” She details Carnap’s ideas and their putative similarity to Kant’s. In her conclusion, she reminds us that Carnap differs in his radical empiricism and reliance on modern logic and set theory.

I am truly amazed that such a perspective and project we see in Russell and Carnap could be conceived and taken seriously. What has phenomenalism and logical reductionism have to do with real science? It should evident how ideological images of science are linked to dogmatic philosophical positions, taking up decades of effort before bumping into the inevitable dead end.


Deviant Logic, Fuzzy Logic: Beyond the Formalism. Chicago; London: The University of Chicago Press, 1996. (Expanded edition of 1974 Deviant Logic.) The linked document includes the table of contents and Introduction (pp. ix-xix).

Haack begins her introduction by outlining how her perspective has altered since the 1974 publication of Deviant Logic, the essays of which are included in this book. She remains convinced of its core contentions, and while none of the deviant systems threaten the position of classical logic, she now approaches the possibility of the revisability of logic differently, less influenced by Quine. Rather than restricting focus to analyticity and meaning, the deeper questions of the relation of logic to semiotics in general should be addressed, Haack is now strongly influenced by Peirce, a pioneer in the development of modern logic, who conceived of logic more broadly than Frege, and gave serious consideration to the problem of vagueness. .She summarizes her critique of fuzzy logic. (See below.) Haack prefers the approach of adopting a non-classical semantics within the framework of classical logic. She is skeptical of Meinongian logic. She is dissatisfied with the treatment of possible worlds, unreal objects, fictional discourse, and belief. By way of the paradoxes of material implication, issues of relevance logic, and paraconsistent logic, Haack reveals her strong skepticism about Graham Priest’s dialethic logic, in its weaker and well as its stronger unorthodoxy in addressing the logical paradoxes. She reserves special disdain for feminist approaches to logic. (See footnote 22 viz. accusations of classical logic enforcing dualism and oppression. Priest is also guilty of this preposterous politicization of logic.) Finally, she clarifies her openness to the possibility of the revisability of classical logic, given that the history of logic is far more variegated than generally recognized. If such revision convincingly advances, Haack speculates that it will come about via a combination of deviance and extension (pace Quine). Promising areas include enquires into propositional attitudes, modality, quantification, and the covertly metalinguistic.

Even for those not versed in the technicalities of logical systems, this is fascinating and revealing. It seems that formal logic in any of its systems is on its strongest ground in formulating truth-preserving inferences. The question remains as to its relationship to ontology, epistemology, and extraformal reasoning (where almost all rational deliberation resides), and we must add the extra-formal interpretation and understanding of formalisms themselves. Then there is the question of the relationship of formal logic so conceived to broader conceptions of logic (involving metaphysical questions and specific content) that are generally considered outside the scope of what logic is today. Hegel is conspicuously absent from all of this discussion. Presumably there is some way of correlating if not reconciling all of this, but what that consists of eludes me here. The pursuit of formalized schemes of inference is important and illuminating in its own right, but it does not seem to improve markedly the extra-formal reasoning processes of logicians, philosophers, theorists, and intellectuals in general. There is a perceptible gap between these two realms that suggest something about the cognitive dimension of the division of labor and social organization in general, and ideology, that has yet to be seriously engaged by analytical philosophy.

See also her comments on ‘feminist logic’ (on this site).

Do We Need ‘"Fuzzy Logic’?” (1979), reprinted in Deviant Logic, Fuzzy Logic: Beyond the Formalism (Chicago; London: The University of Chicago Press, 1996), pp. 232-242, with introduction (1996), pp. 229-231. (Expanded edition of 1974 book.)

The essay begins with contrapoised quotes by Frege and F. C. S. Schiller. (Frege contrasts the flexibility of ordinary language and the rigidity of formal logic and acknowledges the need for both, which serve distinct purposes. Schiller argues that formal logic is too limited to handle real-life thinking.) Haack distinguishes between two projects associated with fuzzy logic: (1) novel interpretations of many-valued base logics; (2) new logical systems in which the truth values themselves are fuzzy sets. Her criticisms are directed to the second category. Classical logic is held to be inadequate to deal with real-world arguments involving vagueness or indeterminacy. The alternative is to formalize informal arguments or loosen up classical logic. The second type or stage of fuzzy logic is a radical departure from classical logic, but even more so, the very nature of logic as conceived in classical logic. Zadeh, the creator of fuzzy logic, also introduced “linguistic truth-values” grouping the ranges of degrees of truth (true, very true, not very true, etc.). Truth-values then become subjective, and the result is approximate inference. This violates, according to Haack and others, the very purpose of formal logic. She argues that fuzzy logic is both methodologically extravagant and linguistically incorrect. Fuzzy logic introduces further complexities rather than reducing the complexities of informal argument. It is incapable of logically regimenting multidimensional vagueness, and it imposes artificial precision. The linguistic expressions for the desired notion of degrees of truth are hopelessly confused.

In the 1996 introduction to the book’s section on fuzzy logic, Haack recapitulates her argument, and concludes that, as fuzzy logic does not attempt to represent truth-preserving inferences, it is not really a logic at all.

Haack has more to say her introduction to the book itself, also placing fuzzy logic into the larger issue of the various conceptions of logic.

To the extent that I understand this exposition, Haack’s argument convinces me. This leaves open the question of how to relate formal logic to the conceptual structuration of real-life thinking, and formalization to the extra-formal in general.

Philosophy of Logics. Cambridge: Cambridge University Press, 1978.

See her concluding comments on Logic and thought (on this site).

About Susan Haack:

Susan Haack: Reintegrating Philosophy, edited by Julia F. Göhner, Eva-Maria Jung. Cham: Springer, 2016.

Thinking about Logic: Classic Essays, edited by Steven M. Cahn, Robert B. Talisse. Scott F. Aikin. Boulder, CO: Westview Press, 2011.

Philosophy of Paraconsistency & Associated Logics (Web Guide)

Lewis Carroll’s Logic Games, Mathematical Recreations, Puzzles & Paradoxes

Argumentation & Controversies: Selected Bibliography

Secular Humanism—Ideology, Philosophy, Politics, History: Bibliography in Progress

Historical Surveys of Atheism, Freethought, Rationalism, Skepticism, and Materialism: Selected Works

Atheism / Freethought / Humanism / Rationalism / Skepticism / Unbelief / Secularism / Church-State Separation Web Links

Philosophical Style: Selected Bibliography

Biographical and Psychological Dimensions of Philosophy: Selected Bibliography

Philosophy of History of Philosophy & Historiography of Philosophy: Selected Bibliography

American Philosophy Study Guide

Vienna Circle, Karl Popper, Frankfurt School, Marxism, McCarthyism & American Philosophy: Selected Bibliography

Positivism vs Life Philosophy (Lebensphilosophie) Study Guide

Philosophy for the 21st Century: A Provincial Bibliography

Home Page | Site Map | What's New | Coming Attractions | Book News
Bibliography | Mini-Bibliographies | Study Guides | Special Sections
My Writings | Other Authors' Texts | Philosophical Quotations
Blogs | Images & Sounds | External Links

CONTACT Ralph Dumain

Uploaded 21 April 2018
Last update 4 January 2024
Previous update 14 January 2023

©2018-2024 Ralph Dumain