WorksheetsLogic test 1
Total questions: 27
Worksheet time: 16mins
Valid Arguement:
An argument where it is impossible for the premises to be true and the conclusion false
a valid argument with true premises
a sentence which is true in every row of a truth table
true in all possible ways
Sound Argument
an argument where it is impossible for the premises to be true and the conclusion falls
a valid argument with true premises
true in all possible worlds
an argument where two sentences are tautologically equivalent when the truth tables for the statements are identical
The following is an example of...
P1 Jackie's baby is a turtle or a frog
P2 Jackies baby is not a frog
C. Jackies baby is a turtle.
Valid Argument
Sound Argument
The following is an example of...
P1 Jackies baby is a girl or boy
P2 Jackies baby is not a boy
C Jackies baby is a girl.
Sound Argument
Valid Argument
Logical Truth:
true in all possible worlds
must always be true
a sentence which is true in every row of a truth table
Logical Necessity:
could be true
Must always be true
when the truth tables for the statements are identical
logical possibility:
could be true
logical possibility is not a physical possibility
logical possibility is a physical possibility
tautology:
a sentence which is true in every row of a truth table
the truth tables for the statements are identical
Tautological Equivalence:
when the truth tables for the statements are identical
Q is equivalent of P if when P is true, Q is always true as well
a sentence which is true in every row of a truth table
Tautological Consequence:
Q is a tautological consequence of P if when P is true, Q is always true as well
Q is a tautological consequence of P if when P is true, Q is false
P is a tautological consequence of Q if when Q is true, P is always true as well
Q is not a tautological consequence of P if when P is true, Q is always true as well
negation, ¬:
(a)
Conjunction, ∧
(a)
Disjunction ∨
(a)
Simplification:
Associativity of ∧
P ^( Q ^ R) <=> (P ^Q) ^R
<=> P ^ Q ^ R
P ^ Q <=> Q ^ P
P^P <=> P
Simplification:
Associativity of v:
P v (Q v R) <=> (P v Q) v R
<=> P v Q v R
P v Q <=> Q v P
P v P <=> P
Simplification:
Commutativity of ^:
P ^(Q ^ R) <=> ^ R
<=> P ^ Q ^ R
P ^ Q <=> Q ^ P
P ^ P <=> P
Simplification:
Commutativity of v:
P v( Q vR) <=> (P v Q) v R
<=> P v Q v R
P v Q <=> Q v P
P v P <=> P
Simplification:
Idempotence of ^
P ^ (Q ^ R) <=> (P ^ Q) ^ R
<=> P ^ Q ^ R
P ^ Q <=> Q ^ P
P ^ P <=> P
Simplification:
Idempotence of V
P v( Q v R) <=> (P v Q) v R
<=> P v Q v R
P v Q <=> Q v P
P v P <=> P
Negation Normal Form/NNF
¬(¬(¬A ∧ B) ∧ C) <=> ¬(( ¬¬A∧¬B)∧C)
<=> ((A ∧¬B)∧ C)
<=> ¬(A∧¬B)∨ ¬C
<=> (¬A ∨ B) ∨ ¬C
¬(¬(¬A ∧ B) ∨ C) <=> ¬(( ¬¬A∧¬B)∧C)
<=> ((A ∧¬B)∧ C)
<=> ¬(A∨¬B)∨ ¬C
<=> (¬A ∨ B) ∨ ¬C
De Morgans Laws:
¬¬ P <=> P
¬ ( P ∧ Q) <=> (¬P ∨¬Q)
¬(P∨Q) <=> (¬P ∧¬Q)
¬¬P ∨ Q <=> P∧Q
Identity Elimination ( =Elim_
P(n)
:
n=m
:
>P(m)
n=n
Pi
:
P1 v... Pi v...v Pn
Identity Introduction ( = Intro)
n=n
P
:
P
Disjunction Introduction ( V Intro)
Pi
:
P1 v... Pi v... v Pn
P1
∇
Pn
:
P1 ^... ^ Pn
P1 ∧...∧ Pi ∧...∧Pn
:
Pi
Conjunction Introduction ( ∧ Intro)
Pi
:
P1∨... Pi
P1
⊽
Pn
:
P1 ∧...∧Pn
P1 ∨...∨Pn
P1
:
s
Pn
:
s
:
s
Disjunction Elimination ( v Elim)
P1 ∨...∨Pn
P1
:
s
Pn
:
s
:
s
P1
V
Pn
:
P1 ^... ^Pn
Pi
:
P1 v... Pi v....vPn
Conjunction Eliminations ( ^ Elim)
P1 ∨...∨Pn
P1
:
s
Pn
:
s
:
s
P1 ∧...∧Pi∧... ∧Pn
:
Pi
Pi
:
P1 ∨... Pi ∨... ∨ Pn
