Beware of the "Black Swan" fallacy. Deductive logic is tautological; there is no way to get a new truth out of it, and it manipulates false statements as readily as true ones. If you fail to remember this, it can trip you — with perfect logic. The designers of the earliest computers called this the "Gigo Law," i.e., "Garbage in, garbage out."
Inductive logic is much more difficult — but can produce new truths.