etorreborre/s99 — pull request #1 by runeflobakk (2012-03-06 10:10:52+00:00)
Title: Found an error in the truth table for logical implication

Fixed truth table for impl(). Logical implication is false if *and only if* the first argument is T and the second is F.

Ref: http://simple.wikipedia.org/wiki/Implication_%28logic%29

Thanks for this awesome learning tool! :)