A '''syllogism''' is a [[logic]]al [[argument]] that necessarily follows if two [[premise]]s are true.
A '''syllogism''' is a [[logic]]al [[argument]] that necessarily follows if two [[premise]]s are true.
−
"All cats are mammals."
+
:"All cats are mammals."
−
"Fluffy is a cat."
+
:"Fluffy is a cat."
−
Therefore
+
:Therefore
−
Fluffy is a mammal.
+
:Fluffy is a mammal.
As [[linguistic]] tools, syllogisms are built from category words such as "all" "none" "some".
As [[linguistic]] tools, syllogisms are built from category words such as "all" "none" "some".
−
"No conservative voted for Obama"
+
:"No conservative voted for Obama"
−
"Andy is a conservative"
+
:"Andy is a conservative"
−
therefore, "Andy did not vote for Obama".
+
:therefore,
+
:"Andy did not vote for Obama".
One has to be careful, however, what categories are applied and assumed.
One has to be careful, however, what categories are applied and assumed.
−
"No conservative voted for Obama"
+
:"No conservative voted for Obama"
−
"John did not vote for Obama"
+
:"John did not vote for Obama"
−
Therefore
+
:Therefore
−
"John is a conservative." is an example of an incorrect syllogism, as the exclusive category "no Conservative" does not rule out other people not voting for Obama.
+
:"John is a conservative." is an example of an incorrect syllogism, as the exclusive category "no Conservative" does not rule out other people not voting for Obama.