## Notre Dame Journal of Formal Logic

### The Expressive Truth Conditions of Two-Valued Logic

Stephen Pollard

#### Abstract

In a finitary closure space, irreducible sets behave like two-valued models, with membership playing the role of satisfaction. If f is a function on such a space and the membership of $fx_1 ,\ldots, x_n$ in an irreducible set is determined by the presence or absence of the inputs $x_1 ,\ldots, x_n$ in that set, then f is a kind of truth function. The existence of some of these truth functions is enough to guarantee that every irreducible set is maximally consistent. The closure space is then said to be expressive. This paper identifies the two-valued truth functional conditions that guarantee expressiveness.

#### Article information

Source
Notre Dame J. Formal Logic, Volume 43, Number 4 (2002), 221-230.

Dates
First available in Project Euclid: 17 January 2004

Permanent link to this document
https://projecteuclid.org/euclid.ndjfl/1074396307

Digital Object Identifier
doi:10.1305/ndjfl/1074396307

Mathematical Reviews number (MathSciNet)
MR2034747

Zentralblatt MATH identifier
1050.03008

Subjects
Primary: 03B22: Abstract deductive systems
Secondary: 03B05: Classical propositional logic

#### Citation

Pollard, Stephen. The Expressive Truth Conditions of Two-Valued Logic. Notre Dame J. Formal Logic 43 (2002), no. 4, 221--230. doi:10.1305/ndjfl/1074396307. https://projecteuclid.org/euclid.ndjfl/1074396307

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