Deductive reasoning

From general propositions:

• All ravens are black birds.
• For every action, there is an equal and opposite re-action

• This bird is black, therefore it is a raven.
• This billiard ball will move when struck with a cue.

In contrast to inductive reasoning, the conclusions of deductive reasoning are as valid as the initial assumption.

Deductive reasoning was first described by the ancient Greek philosophers such as Aristotle.

See also

• Inductive reasoning
• Logic