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What is Logic?
Facts are the building blocks of logical thought. Identification, interpretation and
analysis of facts are of crucial importance to logical thought.
Where do facts come from?
1. Personal experience
2. Recorded experience of others
3. The ability to reason
But beware – whether you get your facts from an outside source or from your own recollection,
remember -- mistakes can happen. Faulty logic can happen because of familiarity with a
subject, or because it is a personal experience, you can often be too hasty in forming a decision
or judgment.
Be critical: examine the facts you are using carefully and thoroughly.
Use reason: logical and rational thought can be divided into two categories, induction
and deduction.
Induction:
Inductive reasoning allows you to move from particular facts to general facts – from the known
to the unknown. It has three basic steps:
1. Careful gathering of all available information
2. Separating the important form the unimportant
3. Reaching a conclusion from the pertinent data
Car mechanics or physicians, for example, use inductive thought. They go from the facts that
you provide and those they can discover – separating the important from the unimportant as
they go – and then make a diagnosis based on that information.
Deduction:
Deduction moves from the abstract to the concrete, from the general to the specific. For
example:
All humans are mortal
I am human
Therefore I am mortal
The above three line statement is called a syllogism, the written form of deductive thought. The
first statement is the major premise arrived at inductively. The second statement is a minor
premise, an example about which you are making a judgment and the third is the conclusion. In
deductive reasoning if both major and minor premises are true, and the rules of good logic are
followed, the conclusion is generally correct. But remember – mistakes can happen!
Developed by LLCC Learning Lab