Logical Terms: Difference between revisions

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(Added "tautology" in order to explain "identity".)
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;[[deduction]]: A line of reasoning from the general to the specific.
===Types of Inferences===
;[[induction]]: A line of reasoning from the specific to the general.
 
;[[tautology]]: A sentence which only makes one factual claim in several different ways, also known as one way to "state the obvious".  For example:
;[[logic|deduction]]: A line of reasoning from the general to the specific.  If you know that all men are mortal and Socrates is a man then you can deduce that Socrates is also mortal.
;[[concept formation|induction]]: A line of reasoning from the specific to the general.  If you see men growing old and dying then you can induce that all men are mortal.
 
Both induction and deduction are based on the [[identity|law of identity]].
 
===Tautologies===
 
A tautology is a sentence which repeats the same information.  For example:
*"This bachelor is not married."
*"This bachelor is not married."
*"They fatally died."
*"They fatally died."
*"This tautology is circular."
*[[#Tautology|"This is an example of a tautology."]]
 
The [[identity|law of identity]] dictates that all truths must ultimately be tautological, although some tautologies can be false.  All three [[axioms]] are explicitly tautological.

Latest revision as of 00:54, 23 May 2014

Types of Inferences

deduction
A line of reasoning from the general to the specific. If you know that all men are mortal and Socrates is a man then you can deduce that Socrates is also mortal.
induction
A line of reasoning from the specific to the general. If you see men growing old and dying then you can induce that all men are mortal.

Both induction and deduction are based on the law of identity.

Tautologies

A tautology is a sentence which repeats the same information. For example:

The law of identity dictates that all truths must ultimately be tautological, although some tautologies can be false. All three axioms are explicitly tautological.