Unit 2 Flashcards
Statements can be true: example
The earth is round
Statements can be false:example
I am 7 feet tall
Statements can be nonsense: example
The gyre orld the mupper until it wret
Self-supporting 1
Self Report: I believe that the sky is blue
Self-Supporting 2
True or false by logical structure (tautology): The sky is blue or is not blue
Self-Supporting 3
True or false by definition: “all triangles are 3 sided figure” - true “that triangle is an octagon” - false
Supported Statement 1
Authority
Supported Statement 2
Experience/Observation
Supported Statement 3
Deduction
Consistency
Two statements can be true at the same time.
Oranges are orange. Grass is green
Implication
If statement P implies statement Q, and if statement P is true, then the statement Q must be true
Logical Equivalence
The first must imply the second and the second must imply the first.
No Buddhists are Christians.
No Christians are Buddhists
Independence
If statements have nothing to do with the true or falseness of another statement then they are independent.
All people have 2 legs
All tricycles have 3 wheels.
Real disagreement
Both statements can’t be true at the same time
Apparent Disagreement
Differences in opinion or perception.
P1: I think logic is easy
P2: I think logic is hard