Line 43: |
Line 43: |
| | | |
| ===Step 3 (Optional)=== | | ===Step 3 (Optional)=== |
| + | |
| + | Check that <math>A \Rightarrow A</math> is a theorem of classical propositional calculus. |
| | | |
| <pre> | | <pre> |
− | Check that A => A is a theorem of classical propositional calculus.
| |
− |
| |
| A A | | A A |
| o---o o---o | | o---o o---o |
| | | | | | | |
| @ = @ = @ | | @ = @ = @ |
| + | </pre> |
| | | |
| Check. | | Check. |
− | </pre>
| |
| | | |
| ===Step 4=== | | ===Step 4=== |