Ideas from 'Gentzen's Analysis of First-Order Proofs' by Dag Prawitz [1974], by Theme Structure

[found in 'A Philosophical Companion to First-Order Logic' (ed/tr Hughes,R.I.G.) [Hackett 1993,0-87220-181-3]].

Click on the Idea Number for the full details    |     back to texts     |     expand these ideas

5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
Logic is based on transitions between sentences
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives
Natural deduction introduction rules may represent 'definitions' of logical connectives
5. Theory of Logic / H. Proof Systems / 4. Natural Deduction
In natural deduction, inferences are atomic steps involving just one logical constant