Concept
Propositional formula
Overview
type of logical formula in propositional logic
Overview adapted from Wikipedia (CC BY-SA 4.0; see the article history for authors).
Possible passages
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In this case, however, the predicate and subject are not merely reversed, but one of them is changed. Instead of [A] and [B], the terms of the new proposition are [a thing which is not B], and [A]. The original proposition, Some A _is not_ B, is first changed into a proposition æquipollent with it, Some A _is_ "a thing which is not B;" and the proposition, being now no longer a particular negative, but a particular…
John Stuart Mill, A System of Logic
States what Propositional formula is.
This is a definite proposition which, with certain limitations, is true. But the truth-value of the proposition does not immediately concern us. Instead of mercury put a mere letter which is the name of some undetermined thing: we get-- The specific heat of _x_ is 0·033. This is not a proposition; it has been called by Russell a propositional function. It is the logical analogy of an algebraic expression. Let us…
Alfred North Whitehead, The organisation of thought, educational and scientific
States what Propositional formula is; the author is tied to Propositional formula in the knowledge graph.
The content of a belief, when expressed in words, is the same thing (or very nearly the same thing) as what in logic is called a "proposition." A proposition is a series of words (or sometimes a single word) expressing the kind of thing that can be asserted or denied.
Bertrand Russell, The Analysis of Mind
States what Propositional formula is; the author is tied to Propositional formula in the knowledge graph.
Related ideas
- Empiricism
- Analysis
- Artificial intelligence
- Alan Turing
- Law of identity
- Judgment (mathematical logic)
- Propositional variable
- John Locke
- Truth value
- Kurt Gödel
- Logical equivalence
- Law of noncontradiction
- Law of excluded middle
- Formal grammar
- Logical connective
- Propositional logic
- Predicate (grammar)
- Function (mathematics)
- Mathematics
- Modus ponens
- Augustus De Morgan
- Intuitionism
- Sir William Hamilton, 9th Baronet
- William Stanley Jevons
Opposing perspectives
Place in the tradition
Part of Outline of logic.