the paradox of necessary truth, once moreby paul weiss

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The Paradox of Necessary Truth, Once More by Paul Weiss Review by: Alonzo Church The Journal of Symbolic Logic, Vol. 23, No. 4 (Dec., 1958), p. 442 Published by: Association for Symbolic Logic Stable URL: http://www.jstor.org/stable/2964031 . Accessed: 18/06/2014 20:32 Your use of the JSTOR archive indicates your acceptance of the Terms & Conditions of Use, available at . http://www.jstor.org/page/info/about/policies/terms.jsp . JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact [email protected]. . Association for Symbolic Logic is collaborating with JSTOR to digitize, preserve and extend access to The Journal of Symbolic Logic. http://www.jstor.org This content downloaded from 194.29.185.109 on Wed, 18 Jun 2014 20:32:48 PM All use subject to JSTOR Terms and Conditions

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Page 1: The Paradox of Necessary Truth, Once Moreby Paul Weiss

The Paradox of Necessary Truth, Once More by Paul WeissReview by: Alonzo ChurchThe Journal of Symbolic Logic, Vol. 23, No. 4 (Dec., 1958), p. 442Published by: Association for Symbolic LogicStable URL: http://www.jstor.org/stable/2964031 .

Accessed: 18/06/2014 20:32

Your use of the JSTOR archive indicates your acceptance of the Terms & Conditions of Use, available at .http://www.jstor.org/page/info/about/policies/terms.jsp

.JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range ofcontent in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new formsof scholarship. For more information about JSTOR, please contact [email protected].

.

Association for Symbolic Logic is collaborating with JSTOR to digitize, preserve and extend access to TheJournal of Symbolic Logic.

http://www.jstor.org

This content downloaded from 194.29.185.109 on Wed, 18 Jun 2014 20:32:48 PMAll use subject to JSTOR Terms and Conditions

Page 2: The Paradox of Necessary Truth, Once Moreby Paul Weiss

442 REVIEWS

applying the functional calculus to atomic and compound sentences of the kind in question. Indeed, the latter would even include synthetic compound sentences, e.g., those of the form 'fx v gx'. On analogous grounds, the author asserts that there is no functional calculus for certain sentence types pertaining to complex particulars and their properties. Thus, stimulating though they are, the ideas developed in this article -

and some of them fall outside the scope of this JOURNAL - do not justify the claim that they "call for a radical reinterpretation of the logical foundations of the functional calculus."

Sellars's second article is an attempt further to clarify and elaborate some of the ideas just referred to; it includes a critique of what is called the notion of "bare particulars," and a defense of the conception that no basic particular can exemplify more than one "simple non-relational universal."

Alston's article contains a critical discussion of Sellars's second essay. CARL G. HEMPEL

PAUL WEISS. The paradox of necessary truth, oiwe more. Philosophical studies (Minneapolis), vol. 7 (1956), pp. 88-89.

Replying to Bar-Hillel (XXI 83), the author reintroduces the "Paradox of Necessary Truth" by another argument. This is based on the assertion that "what is not im- possible might be true or might be false," for which no support is offered. The quoted assertion is multiply ambiguous, and meanings can be found for it which make it true. But taken in the meaning which is required to support the paradox, it would seem to the reviewer that it is obviously false.

In any case, there is no specific system of axioms for modal logic which has actually been proposed by anybody and which Weiss condemns as inconsistent (or Bar-Hillel defends as consistent). ALONZO CHURCH

ROBERT G. TURNBULL. A note on Mr. Hare's "logic of imperatives." Ibid., vol. 5

(1954), pp. 33-35. R. M. Hare in XV 145 observes that inferences involving imperatives and indicatives

may be criticised either because the relations between the contents of the statements or commands involved are not such as to warrant inference, or because commands and statements as such are wrongly combined, e.g. an imperative conclusion drawn from purely indicative premisses. Hare's rules are open to criticism in detail, but there is no obscurity about his main intention. To say, in particular, that some inference is free from faults in the first of the two respects above mentioned but not in the second, would be like saying that a syllogism breaks no rule of distribution but breaks a rule of quality. Turnbull, however, in the present note, writes as if Hare were some- how committed to treating some inferences as valid and invalid at once. In the reviewer's opinion the difficulty which is thus raised in regard to Hare's treatment of imperatives is spurious. A. N. PRIOR

JEAN DE LA HARPE. La logique de assertion pure. Nouvelle encyclop~die philosophique 48. Presses Universitaires de France, Paris 1950, xii + 77 pp.

This booklet develops a special kind of modal logic, whose modalities correspond to various forms of assent or of refusal of assent. The author draws his inspiration from the careful logico-psychological analyses of the judgment in Lalande's Voca- bulaire philosophique and from Poirier's IX 99. It is held that any proposition whatever can be analyzed into a content or "lexis" and an "assertion" (i.e., a state- ment or refusal of assent). In the proposition "P is established," "P is not excluded," P is the lexis and may be translated "that we have such and such a fact" and "is established" or "is not excluded" is the assertion.

The author's knowledge of symbolic logic seems to be restricted to Hilbert and

This content downloaded from 194.29.185.109 on Wed, 18 Jun 2014 20:32:48 PMAll use subject to JSTOR Terms and Conditions