Logical reasoning

In logic, three kinds of logical reasoning can be distinguished: deduction, induction and abduction. Given a precondition, a conclusion, and a rule that the precondition implies the conclusion, they can be explained in the following way:

• Deduction means determining the conclusion. It is using the rule and its precondition to make a conclusion. Example: "When it rains, the grass gets wet. It rained. Therefore, the grass is wet." Mathematicians are commonly associated with this style of reasoning.
• Induction means determining the rule. It is learning the rule after numerous examples of the conclusion following the precondition. Example: "The grass has been wet every time it has rained. Therefore, when it rains, the grass gets wet." Scientists are commonly associated with this style of reasoning.
• Abduction means determining the precondition. It is using the conclusion and the rule to support that the precondition could explain the conclusion. Example: "When it rains, the grass gets wet. The grass is wet, therefore, it may have rained." Diagnosticians and detectives are commonly associated with this style of reasoning.

See also

• Logical fallacy
• Logical argument
• Inference
• Reason, Reasoning
• Defeasible reasoning
• Analogy, Metaphor

References

• T. Menzies. Applications of Abduction: Knowledge-Level Modeling. November 1996