Introduction to Inductive & Deductive Reasoning
​Francis Bacon is credited with introducing inductive reasoning into scientific inquiry in the 17th century.  While he was the first to formalize the concept of a true scientific method, he did not do it without a little help.  The work of Nicolaus Copernicus (1473-1543) and Galileo Galilei (1563-1642) influenced Bacon tremendously.  Inductive reasoning begins with the specific details and observations and uses them to arrive at a principle to explain them.  What we now call the scientific method is largely inductive. 
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Francis Bacon (1561 - 1626)
 The Greek philosopher Aristotle is considered to be the father of deductive reasoning because he actually carved out the entire subject of logic for the first time. He identified the most common and crucial type of reasoning.  He defined for the first time what it means to prove something, to prove it or explain it, objectively, on the basis of facts.

Deductive reasoning is a logical process in which a conclusion is based on the concordance of multiple premises that are generally assumed to be true.
 
Aristotle’s classic example is as follows:
  • All mean are mortal.
  • Socrates is a man.
  • Therefore, Socrates is mortal.​
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Aristotle (384 - 322 BC)
In Aristotle’s example, sometimes referred to as a syllogism, the premises of the argument – that all men are mortal and that Socrates is a man – are true.  Because the premises establish that Socrates is an individual in a group whose members are all mortal, the inescapable conclusion is that Socrates must likewise be mortal.
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