how do the principles and methods of logic bring out the truth?

Answer 1

Logic is about being consistent. As it says on the back of my elementary logic book its about a certain type of consistency - the book gives the example of somebody supporting Arsenal one day and Spurs the next - fickle but not illogical.

Now a propositon, call it P as the logicians always do, is either true or false. If you are inconsistent, sometimes maintaining P sometimes maintaining ¬P (¬ = "not") some of your statements will be false. Some people have maintained that inconsistency is completely fatal for any system of belief because you can prove anything from a contradiction. Bertrand Russell once proved he was God from 2 + 2 = 5
1. 2+2 = 5 so, subtracting 2 from both side of the equation -
2. 2 = 3 so, subtracting 1 -
3. 1 = 2, read "one is two"
4. God and I are certainly two, and form (3) that means that God and I are one. So I am God!

Now how logic can "bring out truth" is by helping you analyse your knowledge, bring out contradiction and correct them. It doesn't "produce" truth as it adds no new propositions to the store of knowledge being analysed: it just says whether they are consitent or not. However it does allow you to examine more thoroughly the implications of the knowledge you already have. "Introducing Einstein" is a good book to give you a realisation of the power of logic. It explains how Einstein came up with relativity theory and you realise on reading it that he came up with it after NO experiments or observations at all - the whole thing was already implicit within existing theories. It was the examination of this and the attempt to make the apparently contradictory observations (that had already taken place) consistent that produce the theory.

Answer 2

By process of elimination.

But logic only brings out a "logical truth". You start with a theoretical problem and filter out contradictions and "false" statements in search of an abolute - "truth". That can be very enigmatic because most of the time people use logic to find the metaphysical truth.

Using logic in metaphysical issues like the soul, God, morality, etc. doesn't get you to an absolute truth but it helps in narrowing down and refining your understanding of things. But then again, that's where you get 500 page volumes on 'justice' and you end up understanding no more than before you started.

Answer 3

in debate

Answer 4

Dear prof, they don't. They just don't.