The Science of Reasoning

Reasoning is an inherent, natural function of the brain. Therefore, to reason about reality is natural. The question is not, “Do we reason?” but, “Does our reasoning lead to us closer to or further from reality?”

I believe a reality exists independently of what I believe about it and while I don’t believe reality is comprehensively known or understood, we know enough to make statements about it. Consider these statements of reality:

• The world is round (even if I believe it is flat)
• 2+2=4 (even if I can't add)
• The planets in our solar system revolve around the sun (even if I don't exist)
• The sun rises in the east and sets in the west (even if I’m blind)
• The earth orbits the sun (even though it seems as if the sun moves around the earth)

The statements above also reveal important characteristics about the nature of reality:

• Reality is independent of belief
• Reality is universal (2+2=4 is the same for everyone, even if they can’t add)
• Reality is not subjective – people don’t define it
• Reality is not contradictory – 2+2 will always equal 4
• Reality is discovered – not invented

Statements about reality are considered true when they agree with the nature of reality, or stated another way, when they don’t contradict the nature of reality. Truth, according to this definition, must correspond with reality.

Reasoning is the process of determining truth. Logic is the study of the methods and principles used to distinguish correct reasoning from incorrect reasoning. Author of several books on logic and mathematics, Irving M. Copi wrote, "The distinction between correct and incorrect reasoning is the central problem with which logic deals."

Put more simply, logic is the science of reasoning.

Still, even our best logic won’t guarantee we will arrive at truth. History provides many examples of beliefs we thought we true, but, later, turned out to be wrong. Nevertheless, by ensuring our logic is correct, I believe we are more likely to get closer to the truth than with incorrect logic.

Reasoning can be deductive or inductive. In a deductive reasoning, a claim is made that is supported by statements which are either true or false. For example, the claim that the Greek Philosopher Socrates was a mortal might be supported in the following manner:

All humans are mortal.
Socrates was a human.
Therefore, Socrates was mortal.

An argument is truth claim supported by collection of true/false statements.

Deductive arguments can be valid or invalid. This is important to understand because deductive arguments can be valid but untrue. For example:

All humans have 3 legs.
Roy is a human.
Therefore, Roy has 3 legs.

The reasoning above has a valid form but the statement that all humans have 3 legs make the conclusion false.

Negating any of the deductive argument’s premises make the entire argument false. On the other hand, if all the statements are true, and the form is valid, as in the Socrates example, then the conclusion is certain and becomes a true statement about reality.

A deductive argument made popular by Dr. William Lane Craig for the existence of God goes as follows:

Whatever begins to exist has a cause.
The universe began to exist.
Therefore, the universe requires a cause.

From the argument above, we can claim Universe must have been caused by a Transcendent Creator.

Deductive reasoning uses general facts to make a specific truth claim.

Sometimes, not all the facts about reality are known or even can be known. In this case, we examine what we do know and make a statement that is probably, but not certainly true.

An inductive argument uses specific facts to make a general truth claim.

For example:

Complexity implies a designer.
The universe is highly complex.
Therefore, the universe probably has a designer

Unlike the deductive argument, in an inductive argument, the statements provide support for the conclusion, but the conclusion doesn't necessarily follow. Inductive arguments are never certain, but evaluated as better or worse based on the strength of their propositions.

Science is based on inductive reasoning.

In summary, reasoning is a skill that can be learned and involves using the Laws of Thought as a foundation to construct a worldview composed of beliefs, opinions and images that are justified by deductive and inductive reasoning.