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Ideas for 'fragments/reports', 'Fallibilism' and 'A Mathematical Introduction to Logic (2nd)'

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2 ideas

5. Theory of Logic / I. Semantics of Logic / 3. Logical Truth

9721	A logical truth or tautology is a logical consequence of the empty set [Enderton]
	Full Idea: A is a logical truth (tautology) (|= A) iff it is a semantic consequence of the empty set of premises (φ |= A), that is, every interpretation makes A true.
	From: Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], 1.3.4)
	A reaction: So the final column of every line of the truth table will be T.

5. Theory of Logic / I. Semantics of Logic / 4. Satisfaction

9994	A truth assignment to the components of a wff 'satisfy' it if the wff is then True [Enderton]
	Full Idea: A truth assignment 'satisfies' a formula, or set of formulae, if it evaluates as True when all of its components have been assigned truth values.
	From: Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], 1.2)
	A reaction: [very roughly what Enderton says!] The concept becomes most significant when a large set of wff's is pronounced 'satisfied' after a truth assignment leads to them all being true.