What is logic?
The study of arguments and inference.
What is the study of arguments and inferences?
Logic
What is an argument?
A collection of propositions, some of which are intended to provide support to the others.
What is a collection of propositions, some of which are intended to provide support to the others?
An argument
What is ‘xor’?
Exclusive ‘or’.
A xor B means “A or B but not both”.
Name for term meaning ‘Exclusive or’?
Xor
What is an inference?
The process of reasoning in which a new belief is formed on the basis of evidence supposedly provided by other beliefs.
What is the process of reasoning in which a new belief is formed on the basis of evidence supposedly provided by other beliefs?
An inference
What is a proposition?
A truth-apt (truth-carrying) statement, either true xor false, that is a premise or conclusion in an argument.
What is a truth-apt (truth-carrying) statement, either true xor false, that is a premise or conclusion in an argument?
A proposition
What is a premise?
A proposition that intends to support another proposition.
What is a proposition that intends to support another proposition?
A premise
What is a conclusion?
A proposition for which a premise(s) intends to support.
What is a proposition for which a premise(s) intends to support?
A conclusion
What is the name of this argument and is it deductively valid?
If P then Q
P
Therefore Q
- Modus Ponens
or
Affirming the antecedent - Yes, deductively valid
What is the form of this argument, and is it deductively valid?
Modus Ponens / Affirming the antecedent
- If P then Q
P
Therefore Q - Yes, deductively valid
What is the name of the argument depicted by this argument, and is it deductively valid?
- If one human is made of mud, then every human is made of mud
- One human is made of mud
- Every human is made of mud
- Modus Ponens or Affirming the antecedent
2. Yes, deductively valid
What is the name of this argument and is it deductively valid?
If P then Q
Not Q
Therefore not P
- Modus Tollens or Denying the Consequent
2. Yes, deductively valid
What is the form of this argument, and is it deductively valid?
Modus Tollens / Denying the Consequent
- If P then Q
Not Q
Therefore not P - Yes, deductively valid
What is the name of the argument depicted by this argument and is it deductively valid?
- If the soul is immortal, then thinking does not depend on brain activity.
- Thinking does depend on brain activity.
- Therefore, the soul is not immortal.
- Modus Tollens or Denying the Consequent
2. Yes, deductively valid
What is the name of this argument and is it deductively valid?
If P then Q
If Q then R
Therefore if P then R
- Hypothetical syllogism
2. Yes, deductively valid
What is the form of this argument, and is it deductively valid?
Hypothetical syllogism
- If P then Q
If Q then R
Therefore, if P then R - Yes, deductively valid
What is the name of the argument depicted by this argument and is it deductively valid?
- If the hallway floor creaks, there is someone in the hallway
- If there’s someone in the hallway, then there’s a burglar in the house
- Therefore, if the hallway floor creaks, there’s a burglar in the house.
- Hypothetical syllogism
2. Yes, deductively valid
What is the name of this argument and is it deductively valid?
If P then Q
Not P
Therefore not Q
- Denying the antecedent
2. No - it is deductively invalid
