Points for Proofs

Proofs are assigned point values between 0 and 4 as follows.

4 Points: Perfect. Would pass an automated proof checker.

3 Points: One or two minor misapplications of rules that could easily be fixed by being more careful. For example:

1    (1) P->-Q     A
2    (2) Q         A
1,2  (3) -P        1,2 MTT
For full credit, there must be an additional line:
1    (1) P->-Q     A
2    (2) Q         A
2    (3) --Q       2 DN
1,2  (4) -P        1,3 MTT

2 Points: The proof includes one or more successful substrategies, but has irremediable flaws. (This is mostly applicable to complex proofs.) For example, having a "false line" (i.e., the sentence on the line does not follow logically from its dependencies) is usually an irremediable flaw.

1 Point: Some correct applications of the rules, but no proof strategy is apparent.

Check your dependency numbers carefully. Mistakes in dependency numbers will cost you points.