* basic structure of a standardized categorical statement:
* quantifier (All, Some, or No)
* Subject category terms
* Linking verb (Copula) (are, are not)
* Predicate category term
* how to standardize a categorical statement
* Step 1 - rephrase non-standard subjects and
predicates so they refer to categories/groups/sets
of things
* Step 2 - rephrase non-standard linking
verbs to forms of "to be"
* Step 3 - if a quantifier is not explicitly
stated, add it (applying the Principle of
Charity as appropriate)
* Step 4 - a statement about a particular
person, place, or thing can be translated
into a categorical statement...
Before: Fred was born in California.
After: All persons who are Fred are persons
who were born in California.
Before: Ana is not a Green party member.
After: No persons who are Ana are persons
who are Green Party members.
* Step 5 - translate stylistic variants into
the equivalent standardized categorical form:
* All A are B.
* No A are B.
* Some A are B.
* Some A are not B.
* going to the white board for 3-circle Venn diagrams!
* METHOD for checking for VALIDITY of Categorical
Syllogisms:
* Translate the statements into standard
categorical statements.
* Draw the 3-circle Venn diagram,
and label each circle
* Draw the 2 premises in the diagram.
* Do the ALL- and NO- style premises
BEFORE the SOME- style premises
* DO NOT PLACE an X in a SHADED AREA
* Test the resulting diagram against the Conclusion.
* Note that an X MUST BE completely inside
an area for it to establish validity!