proofs (introduction) Flashcards
what is a proof
an argument which starts from one or more premises, which are propositions taken for granted for the purpose of the argument, and argues to a conclusion
what is a premise
a simple statement. It can be abstract, a definition or a hypothesis
what are proofs made of
P+P=C
Premise + Premise = Conclusion
what is an ‘A Priori’ Argument
arguments not dependent on experience , but instead deal with concepts
what is a ‘deductive’ argument
it has a logically necessary conclusion –> if the premise is correct the conclusion is correct; there is only one option for the conclusion
what is an ‘analytic’ argument
an argument that offers no new information
give an example of an A PRIORI, DEDUCTIVE, ANALYTIC ARGUMENT
P: Mary is a wife
P: a wife is a married woman
C: Mary is a married woman
what are the STRENGTHS of an a priori, deductive argument (3)
- it has a necessary conclusion, so it is robust
- it is objective and conceptual, so there is no bias
- if the premises are true the conclusion is automatically true
what are the WEAKNESSES of an a priori, deductive argument (2)
- if the premise changes, the whole argument collapses
- just because the argument is logical, does not mean its sound –> it can be robust and weak
What is an ‘A Posteriori’ argument
arguments based on experience; evidence from the real world
what is an ‘inductive’ argument
arguments that come to a probable conclusion, but can be false –> based on experience
what is a ‘synthetic’ argument
the conclusion is not contained within the premises
give an example of an A POSTERIORI, INDUCTIVE, SYNTHETIC argument
P: Mary wears a ring
P: married women wear rings
C: Mary is a married woman
what are the STRENGTHS of an an posteriori, inductive argument (2)
- if the premise changes, the conclusion still stands
- it is based of empirical data and experience
what are the WEAKNESSES of an a posteriori, inductive argument (3)
- it is subjective –> based on experience
- sense data is unreliable, so experience is therefore unreliable
- the conclusion is probable, because its based on experience rather than logic