PHL145H5 Lecture 2: Lecture 2
Document Summary
Is: a) group of one or more claims to support, b) one further claim. Not just one claim, but a number of claims working towards an answer. The premise is the claim used to support the conclusion. A deductively valid argument: if (hypothetically) all of its premises are true, then its conclusion must be true. Eg: all dogs are mammals, fido is a dog (both premises are true). Therefore fido is a mammal (then conclusion must be true) Eg: all fish are mammals, this elephant is a fish. This is still a valid argument, but its not true. The definition does not require that either the premises or the conclusion of a valid argument be true. Does not tell you what happens if one or more premises is false: does not say that if the premises are false that the conclusion is automatically false, true content = true conclusion, but not falsehood.
