Conditional Statements Flashcards
What is a Conditional Statement?
If the first condition is met, then the second must follow.
Sufficient Condition
Satisfying a sufficient condition is enough to guarantee that a necessary will follow.
Necessary Condition
For a sufficient condition to be satisfied, a necessary condition is required.
If
Sufficient
When
Sufficient
Whenever
Sufficient
All
Sufficient
Any
Sufficient
Each
Sufficient
Every
Sufficient
Then
Necessary
Only
Necessary
Only if
Necessary
Only when
Necessary
Needs
Necessary
Requires
Necessary
Must
Necessary
If and only if
Bi-Conditional Statement
Unless
Negate Necessary Condition
Until
Negate Necessary Condition
Without
Negate Necessary Condition
Except
Negate Necessary Condition
Contrapositive
Valid Inference
Switch & Negate.
Denying the necessary is enough to conclude that a sufficient will not follow.
Fallacy of the Inverse
Invalid Inference.
Negating both sides without switching.
Saying that we don’t have the sufficient condition, does not allow us to conclude we don’t have the necessary condition.
Fallacy of the Converse
Invalid Inference.
Switching both sides without negating.
Affirming the necessary condition doesn’t allow us to conclude that the sufficient is true.
Valid affirmation
Valid inference.
If the sufficient condition is true, then the necessary condition must be true.
Transitive Property
When a necessary condition is identical to the sufficient condition of another conditional statement, they can be combined.
Transitive fallacy
Two necessary statements, matching each other.
Invalid inference.
