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5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives

[general role and status of logical connectives]

27 ideas
'And' and 'not' are non-referring terms, which do not represent anything [Fogelin on Wittgenstein]
My fundamental idea is that the 'logical constants' do not represent [Wittgenstein]
The inferential role of a logical constant constitutes its meaning [Hanna on Gentzen]
The logical connectives are 'defined' by their introduction rules [Gentzen]
Each logical symbol has an 'introduction' rule to define it, and hence an 'elimination' rule [Gentzen]
We need to know the meaning of 'and', prior to its role in reasoning [Belnap on Prior,AN]
Prior's 'tonk' is inconsistent, since it allows the non-conservative inference A |- B [Belnap on Prior,AN]
Prior rejected accounts of logical connectives by inference pattern, with 'tonk' his absurd example [Read on Prior,AN]
Maybe introducing or defining logical connectives by rules of inference leads to absurdity [Hacking on Prior,AN]
'', '&', and 'v' are truth functions: the truth of the compound is fixed by the truth of the components [Jackson]
If logical truths essentially depend on logical constants, we had better define the latter [Hacking]
With a pure notion of truth and consequence, the meanings of connectives are fixed syntactically [Hacking]
Truth-functors are usually held to be defined by their truth-tables [Bostock]
Natural deduction introduction rules may represent 'definitions' of logical connectives [Prawitz]
Logical concepts rest on certain inferences, not on facts about implications [Fine,K]
Classical connectives differ from their ordinary language counterparts; '∧' is timeless, unlike 'and' [Shapiro]
Formalising arguments favours lots of connectives; proving things favours having very few [Burgess]
The nature of each logical concept is given by a collection of inference rules [Correia]
Logical connectives contain no information, but just record combination relations between facts [Read]
The connectives are studied either through model theory or through proof theory [Mares]
Define logical constants by role in proofs, or as fixed in meaning, or as topic-neutral [Sider]
Wittgenstein reduced Russell's five primitive logical symbols to a mere one [O'Grady]
Connectives link sentences without linking their meanings [MacBride]
Natural language includes connectives like 'because' which are not truth-functional [McGee]
Standardly 'and' and 'but' are held to have the same sense by having the same truth table [Rumfitt]
The sense of a connective comes from primitively obvious rules of inference [Rumfitt]
In specifying a logical constant, use of that constant is quite unavoidable [Rumfitt]