Single Idea 10984

[catalogued under 5. Theory of Logic / B. Logical Consequence / 1. Logical Consequence]

Full Idea

If classical logic insists that logical consequence is just a matter of the form, we fail to include as valid consequences those inferences whose correctness depends on the connections between non-logical terms (such as 'round' and 'square').

Gist of Idea

Logical consequence isn't just a matter of form; it depends on connections like round-square

Source

Stephen Read (Thinking About Logic [1995], Ch.2)

Book Reference

Read,Stephen: 'Thinking About Logic' [OUP 1995], p.53


A Reaction

He suggests that an inference such as 'round, so not square' should be labelled as 'materially valid'.