Running head: INFLUENTIAL FACTORS OF HUMAN NATURE
Jennifer R. Webb
Influential Factors of Human Nature
PSYC 4303 Theories of Personality
Professor Engelsvold
January 3rd, 2017
1
INFLUENTIAL FACTORS OF
Rules of Replacement I
Rule of Replacement
A rule consisting of two logically equivalent
statement forms by means of which the
conclusion of an argument is derived from the
premises
Logical equivalenc
Conditional Proof
A. Conditional Proof
A method of proof that consists of assuming the
antecedent of a required conditional statement
Much faster than direct methods of proof
Ideal for arguments which
Truth Tables for Propositions
Steps for determining every possible truth-value
of a compound statement, as stated in a truthtable
1. Determine the number of lines
The number of lines in a truth-table
Venn Diagrams
Venn diagrams allow us to demonstrate
the truth of categorical syllogisms in a
most evident way
As categorical syllogisms involve three
terms, Venn Diagrams reflecting their
meaning must
Rules and Fallacies
Aristotle was the first to delineate rules for valid
argumentation
If an argument breaks a logical rule it is
fallacious
Some texts list the fallacy of equivocation, or
the use of
Symbols and Translation
Operators/Connectives
Symbols used to connect simple propositions
in propositional Logic
Propositional Logic
Logic wherein the fundamental elements are
whole statements represe
Standard Form, Mood, and Figure
Syllogism
A Deductive argument consisting of two
premises and one conclusion
P2
All Doctors are Former Students
Some Professors are Doctors
C
Some professors are former
Logical Operations
Conversion, obversion, and
contraposition are operations that can be
performed on a categorical statement
resulting in a new statement that may or
may not have the same meaning or t
Components of Categorical Propositions
Categorical Proposition:
A proposition that relates two classes or
categories, designated the subject and
predicate respectively; all or part of the
first class
Argument Forms: Proving Invalidity
Argument Form
An arrangement of words or letters such
that the uniform substitution of terms or
statements will produce an argument
Every substitution of terms for
Definitions
Logic
The science that evaluates the validity of
arguments
Argument
A group of statements wherein at least
one statement (the premise) is claimed as
support for one other statement (the
co
Truth Tables for Arguments
Truth tables provide a standard technique for
determining the validity of arguments
Truth Tables for Arguments
Steps for determining every possible truth-value
of a compound
Traditional Square of Opposition
Traditional Square of Opposition
An arrangement of lines that illustrates
logically necessary relations among 4
kinds of categorical propositions, and
presupposes that
Truth, Validity, Strength
Every argument makes two basic claims:
(1) A factual claim, and (2) an inferential
claim.
The inferential claim is more important
We will not even test the factual claim if
t
Recognizing Arguments
Arguments must contain:
1. Premise(s)containing evidence, or
reasons
2. A Conclusionfollows from evidence
Recognizing Arguments
Factual Claim
A claim that something is true
Infer
Definitions of Logical Operators
Truth Function
Any compound proposition whose truth
value is completely determined by the
truth values of its components
Logical operators (~, , v, ,
truth functions.
Aristotle and Boole
Should Universal Propositions (A, E) be
interpreted so that the things talked about
actually exist? Do they have existential
import?
All of U2s songs are ingenious.
All Dragons hav
Natural Deduction
Natural Deduction is a method for establishing
the validity of propositional type arguments that
is both simpler and more enlightening the
method of truth tables
Resembles geometric
Argument Forms and Fallacies
Argument Form
An arrangement of statement variables and
operators such that the uniform replacement of
the variables by statements results in an
argument
Valid Argument Fo
Translating into Categorical Form
Many statements in common speech/writing
may be translated into categorical form.
Such translations are valuable because they
call attention to the valid logical impl
Extended Arguments
Extended arguments in popular
publications are often mixed with
opinions, reports, illustrations, etc.
For our purposes we will number
each sentence in a paragraph and
diagram the
Deduction and Induction
Deductive Argument
An argument which involves the claim that
it is impossible for the conclusion to be
false given that the premises are true
Inductive Argument
An argument whi