Aristotle: Laws of Thought

Philosophy as laws of thought
Aristotle was the first person to investigate the patterns and processing of reason. He discovered (some would say invented) logic. For that alone, he counts high in the pantheon of the most influential people in history. Logic provides the basis for proof and demonstration using natural language. Prior to Aristotle, mathematicians had shown arithmetic and geometrical means to proof. It was the power of such abstract proofs that led Plato to place an inscription over the front gate of the Academy reading; "Let no one enter who is not a geometer." From this background, Aristotle extended the formal study of reasoned proof to a method that applies formal analysis to real human language. Philosophy, science, and technology have followed the path pioneered by Aristotle ever since.

Aristotle wrote several extensive works on logic, which taken together are known as The Organon or the instrument, by which which he meant that logic is an instrument for advancing knowledge.

Aristotle was not merely pointing out ways that people should think; he was describing the fundamental principles by which thought can occur at all. At this foundation he marked three laws of thought, which remain basic in logic to the present. These laws are:

1. The Law of Identity - A is A

Everything is the same as itself; or a statement cannot not remain the same and change its truth value.

2. The Law of Non-Contradiction - NOT (A and not A)

Nothing can both exist and not exist at the same time and
in the same respect; or no statement is both true and false.

3. The Law of Excluded Middle - Either (A or not A)

Something either exists or does not exist; or every statement
is either true or false.

These are given not just as nice rules of thumb to follow or ways that one should think. Aristotle identified these as necessary conditions for thought. People sometimes try to produce counter examples to these Laws by pointing out how statements can become true or false depending on the conditions; e.g. "It is raining" might be true now, but was false yesterday" or "it is half way between raining and not-raining." But these attempts always involve changing the reference of the statement. Once we get the reference of the statement clear and explicit, it does not seem possible for a statement to make sense and vioate these laws. At this point, the 2 thousand year debate over the nature of reference begins, and the shape of philosophy is drawn.

Former President Clinton tried to weasle the Laws of Thought when he denied that he had lied to Congress about whether "there is a relationship with my intern" by saying later "it all depends on what is is." Like in the raining example above, he thought that he could make the truth of his stament change because the relationship had ended). Almost everyone could immediately see that he was twisting words beyond sense and digging himself into an even deeper deception. We can see this because logic involves conditions that are common to us all. Even Presidents cannot veto the Laws of Thought.

Next - Learn about Aristotle's Syllogisms

IQ Home

Aquinas
Aristotle
Augustine
Berkeley
Confucius
Descartes
Douglass
Foucault
Hobbes
Hume
Hypatia
Kant
Kierkegaard
Lao Tzu
Leibniz
Locke
Marx
Mill
Montaigne
Pascal
Plato
Protagoras
Rand
Russell
Schopenhauer
Socrates
Spinoza
Thales