Modern Classification of Propositions
Traditional Classification
Basics
Aristotle
Perceived
Every Prop affirmes or denies something of something else
Meaning : Subject - Predicate form
Defects
As perceived
Contrarily
4 prop in Traditional Classification
are general prop
Exception of Singular Prop
Closer Look
Traditional Logician
Failed in analysis
Lacked the distinguishing capabilities between singular proposition from propositions whose subject term is a class.
Aims and Basis
Classification as devised
Separating a proposition from other proposition which do not contain another proposition (s) as a component from those proposition which contain
Simply Stating - Simple prop ( for the former eg ) and Compound Proposition ( latter eg)
Simple Proposition
Defined as
Prop
Not having
Other Prop as a component
Kinds Of
Subjectless
Subject - Predicate
Relational
Class Membership
Asserts
Concept๐ถ
Assertion made
Exclamatory
Fires!
Impersonal
It rains.
States -
Individual ๐
Possess ๐
Quality
๐ Is a singular term
'Subject 'is a singular term
Symbolically : S-P
Relation
Between
2 or more constituents
Term of relation are Subject and Predicate
Terminology
'Sense or direction of relation'
WHERE relation proceeds from something to something
Referent - term from which relation proceeds
Relatum - term to which relation proceeds
During revision If there's a feeling that everything is correct and no edits required. In such case take a walk , BCOZ there's always any scope for improvement and the state of mind is not supportive enough.
Symbolically
R (x,y) ; x- referent , y- relatum
But Nothing Expressed
Concept ๐ถ
Asserts
Individual
Is a member of
Class
Symbolized
a ฮต F
a - Individual ; F - 'any class'
Distinctions
Make a note for this in 10 min. โค
Compound Proposition
Note: All the above example were of affirmative type, denial of simple proposition gives us compound proposition
Negative Proposition
Any Proposition
Negated
We get
Negative Proposition
Propositional
Connectives
~ :Tilde or curl
Variables
'' ~p''
Conjunctive Proposition
Combination
Of any 2 proposition
Truth Functional
"and "
Components
Called
As Conjuncts
Propositional
Connective
"."
Variable
"p.q"
Truth value
Disjunctive Proposition
word
"or"
combines 2 prop
Components
Called as
Disjuncts
Use of "or"
Inclusive
Exclusive
Both Disjuncts can be True
One Disjunct True other False
[weak]
[strong]
Apt Example for this is in book.
Logic Considers "or " in inclusive sense
Propositional
Connective
v - wedge
Variable and connective
p v q
Implicative Proposition
Combination
2 proposition
words "if....then......."
Component
Between
If...then - antecedent
After "then..." - consequent
Propositional
Connective
โ
Form
p โ q
Note : Implicative prop false only when antecedent is true, and the consequent is false.
Equivalent prop
Combination
2 component prop
'if and only if'
materially implying e.o
Propositional
Variable
triple bar
form = 'p triple bar q'
Read some end 2-3 para of this context from book.
True it is only if both conjuncts are true
Number of Times Revised