Logic

Question 1

Define logically valid argument

Answer 1

An argument is logically valid iff there are no possible situations in which all its premises are true and its conclusion false

Question 2

What are atomic sentences in FOL

Answer 2

An atomic sentence in FOL is the result of combining an n place predicate with n occurrences of constants

Question 3

Define counterexample to an argument

Answer 3

A counterexample to an argument is a possible situation in which the premises of the argument are all true and its conclusion false

Question 4

What is an argument

Answer 4

An argument is a set of statements, one of which is a conclusion, and the rest of which are premises

Question 5

A possible situation is a way things actually are or could have been

Answer 5

What is a possible situation

Question 6

Logically possible

Answer 6

A situation is logically possible if it can be fully described without any logical contradiction

Question 7

Sound

Answer 7

An argument is sound iff it is logically valid and has true premises

Question 8

Proposition

Answer 8

A proposition says that things are a a certain way, and is true or false depending on the actual circumstances

Question 9

Names

Answer 9

Refer to particular objects

Question 11

Predicates

Answer 11

Refer to particular activities or relations between objects

Question 12

Truth conditions

Answer 12

How things need to be for a sentence to be true

Question 13

Invalid

Answer 13

If there is a possible situation in which all its premises are true but its conclusion false