Archives - Mathematics: Page 32
Author: amparo enriquez (Thu Jun 16, 2005 3:31 pm)
Title: Logic vs. Common Reasoning
LOGIC MIGHT BE GOOD FOR MATHEMATICS BUT NOT SO GREAT FOR COMMON REASONING
A sequence of ideas link to each other according to certain rules is what we call logic. Ordinary human thinking however depends little on logic. Although both are constructed in a train-like fashion of block of ideas, in logic sequence the elements are either valid or not. In deductive logic every element of the argument has to be right; one cannot have an element that is half right or almost right. A chain of ideas based on deductive logic needs of adequate appropriately connected units to have a correct ending. Human common reasoning however derivates substantially from pure logic.
No sensible person will ever trust a long, thin chain of reasoning. In real life, when we listen to an argument, we do not merely check each separate step; we look to see if what has been described so far seems plausible. We look for other evidence beyond the reasons in that argument. Consider how often we speak of reasoning in terms of structural or architectural expressions, as though our arguments were like the towers Builder build:
- Your argument is based on weak evidence.
- You must support that with more evidence.
- That argument is shaky. It will collapse.
In this way, common sense reasoning differs from “logical” reasoning. When an ordinary argument seems weak, we may be able to support it with more evidence. But there is no way for a link inside a logic chain to use additional support; if it’s not quite right, then it’s absolutely wrong. Indeed, this weakness is actually the source of logic’s own peculiar strength, because the less we base our conclusions on, the fewer possibilities can exist for weaknesses in our arguments. This strategy serves mathematics well, but it doesn’t help us much in dealing with uncertainties. We cannot afford to stake our lives on chains that fall apart so easily.
Although deductive logic offers a good method to apply to common reasoning, as when we notice a wrong link in a chain of ideas; it doesn’t help us to be creative. Nevertheless logic is a valuable tools that helps us think correctly and to avoid cloudy thoughts. Through this process we can interpret and understand our thoughts better. Human thinking seems to be however more analogical than digital while deductive logic is based on digital reason process where elements in a chain are or are not appropriate.