Deviant Logic: Some Philosophical Issues

by Susan Haack

Book by Haack, Susan

Genres: Logic, Philosophy

203 pages, Hardcover

First published January 31, 1975

About the author

Haack is a graduate of the University of Oxford and the University of Cambridge. At Oxford, she studied at St. Hilda's College, where her first philosophy teacher was Jean Austin, the widow of J. L. Austin.
She studied Plato with Gilbert Ryle and logic with Michael Dummett. David Pears supervised her B.Phil. dissertation on ambiguity. At Cambridge, she wrote her Ph.D. under the supervision of Timothy Smiley. She held the positions of Fellow of New Hall, Cambridge and professor of philosophy at the University of Warwick before taking her current position at the University of Miami.
Haack's major contribution to philosophy, in the 1993 book Evidence and Inquiry is her epistemological theory called foundherentism, which is her attempt to avoid the logical problems of both pure foundationalism (which is susceptible to infinite regress) and pure coherentism (which is susceptible to circularity). She illustrates this idea with the metaphor of the crossword puzzle. A highly simplified version of this proceeds as follows: Finding an answer using a clue is analogous to a foundational source (grounded in empirical evidence). Making sure that the interlocking words are mutually sensible is analogous to justification through coherence. Both are necessary components in the justification of knowledge. At least one scholar has claimed that Haack's foundherentism collapses into foundationalism upon further inspection.
Haack has been a fierce critic of Richard Rorty. She wrote a play, We Pragmatists ...: Peirce and Rorty in Conversation, consisting entirely of quotes from both philosophers. She performed the role of Peirce. Haack published a vigorous essay[8] in the New Criterion, taking strong exception to many of Rorty's views, especially his claim to be a sort of pragmatist.
Haack (1998) is highly critical of the view that there is a feminine perspective on logic and scientific truth. She holds that many feminist critiques of science and philosophy are overly concerned with 'political correctness'.
She has written for Free Inquiry magazine and the Council for Secular Humanism. Haack's work has been reviewed and cited in the popular press, such as The Times Literary Supplement as well as in academic journals.

Source

Reviews

[Randal Samstag · Rating 4 out of 5]

Deviant Logic is based on the work Susan Haack completed for a PhD dissertation at Cambridge University. The book was published by Cambridge University Press in 1974. It is a brave book that provides penetrating critiques of some of the most cherished doctrines of the most prominent philosophers of logic of the previous generation; including Quine, Putnam, Dummett, Popper, and Lukasiewicz. While recommending what she calls a ‘radical’ approach to non-classical logics, in the end she opts for classical logic as the logic which best satisfies her pragmatist criteria of simplicity and economy.

While her book, as suggested by the title, considers alternatives to what she calls ‘classical logic,’ she nowhere in the body of the text says exactly what she means by this term. In an appendix she provides a (very handy) semantic summary of a series of logics. This appendix provides matrices which define the truth tables for the various logical connectives in each system; negation, conjunction, disjunction, implication, and identity. Here she presents “2-valued (‘classical’) logic” as the first system considered. But for all of her attempts at clarity, she leaves the system that she is defending otherwise undefined. It is safe to assume that what she has in mind is primarily bivalence (which she abbreviates to ‘PB’ for the principle of bivalence), but that she also includes here the laws of (non-) contradiction (LNC), excluded middle (LEM), and identity, in addition to the truth values for the connectives given in the appendix.

The introductory chapter sets out her goals: to establish the senses in which there could be alternative logics to bivalent logic and to systematically review the plausibility of these alternatives. The alternatives considered include: intuitionist logic, Post’s multivalued logic, minimal logic, Lukasiewicz’s many-valued logic, van Frassen’s propositional languages, and quantum logics. She also considers systems which supplement classical logic: Lewis’s modal logic, epistemic logic, deontic logic, and tense logic. Since the book reviews only logics proposed up to the decade of the 1960s, it does not consider some logics which have become seriously considered in the last 40 years: this includes the general category of paraconsistent logics including the dialetheism of Graham Priest, relevant logic, or fuzzy logic. The latter are considered in papers appended to a subsequent edition of Deviant Logic, but the current review considers only the original text. Given what has come afterwards, her work becomes even more important in being one of the first systematic attempts to address the general question of rivals to standard bivalent logic in a clear and rigorous manner.