Deductive & Inductive Reasoning

1. All cats have tails Felix is a cat Therefore, Felix has a tail Felix has a tail Felix is a cat Therefore, all cats have tails Deductive & Inductive Reasoning

2. Deductive Use universal premises to draw particular & specific conclusions Conclusion doesn’t claim more than is stated in the premises Inductive Use particular premises to prove universal conclusions Conclusion goes beyond what is claimed in the premises Infers conclusions from experience & observation

3. Deductive or Inductive • Partick Thistle are an abysmal team so Scottish football can’t be that great. • Hilary Clinton must be an intelligent woman because she’s a lawyer and all lawyers are clever people. • These pills worked the last time I tried them so they should do the trick. • All dogs are descended from wolves so Fido must be descended from wolves.

4. All inductive arguments are invalid and therefore unsound? • Every schizophrenic patient treated with clozapine has reported a reduction in symptoms. Therefore, clozapine is an effective treatment for schizophrenia. • Discuss

5. Cogency • A cogent argument is one where we not only have a strong argument based on numerous observations but is also one where the premises are true.

6. All observed penguins have been purple, thus all penguins are purple All observed penguins have had feathers, thus all penguins have feathers Cogent or Weak?

7. The London Bombers were terrorists • The London Bombers were Muslim • Thus all Muslims are terrorists • How do we characterise and deal with an argument like this?