7.5. Question 11

Try these first

1. 1.

   Define a valid argument.

   Hint

   Think of the logical structure connecting premises to conclusion.

2. 2.

   What is a tautology?

   Hint

   Consider an example of a statement that cannot be false.

3. 3.

   Which statement is true about valid arguments?

   • The conclusion can be false
   • The conclusion must be true if premises are true
   • The conclusion does not need premises

   Hint

   Think about what it means for an argument to be sound.

4. 4.

   A tautology is:

   • True
   • False

   Hint

   Remember the definition of a tautology.

5. 5.

   Given the premises 'If today is Monday, then it’s raining' and 'It’s Monday', what can you conclude?

   Hint

   Use the principle of conditional statements.

6. 6.

   Consider the argument: 'All cats are animals' and 'Whiskers is a cat', validate the conclusion that 'Whiskers is an animal'.

   Hint

   Examine the premises carefully to see how they relate.