Three three laws of logic l: excluded middle:
Two contradictory views, and certainly a right, there is no "not right" This intermediate state. In this case, a person can not stand, but if you stand, you can not say, "I do not agree with two"
such as:
I think the price is wrong, it can cause damage to brand value. But no price is not right, after all, a lot of selling pressure in front. . .
What is self-contradictory views?
Is the "right price" and "price is not right," two contradictory point of view, there is no "not right" intermediate state.
"You project, can not say successful, I can not say did not succeed." - either in violation of all, if both before and after "successful connotation and extension is not the same" with; or in violation of the law of excluded, if the two "success" is the same concept, because there is no "successful" and "unsuccessful" outside intermediate state.
The right way: "If not earn money to measure, I think that this project is not successful, because the company lost money; there is no growth, but from the point of view, can not say that did not succeed, because we gained valuable experience and lessons learned." .
Reductio ad absurdum
Three steps:
1. Anti-set: turn the assumption does not hold views
2. reductio ad absurdum: assume that reality does not match / or because of his previous hypothesis (false), to derive the current state (true)
3. Cunzhen
such as:
Ren Court Liu Yong large degree due respect in Chodo plain speaking, prompting Longyan rage. Qianlong emperor when the Church made two "paper lots" - the name "lots of life and death." Distinguish between the words "life" on two lots of paper with the "death" word, Liu Yong able to get "lots of Health" that can survive, be able to get "dead lots" will be sentenced cut. In fact, this two "paper lots" are written word "death", which is deliberately make life difficult for the Emperor Qianlong Liu Yong. If you change the others, regardless of where to draw sheet "paper lots" are all mortal; rather clever Liu Yong already guessed that he whim, came out of a "paper lots", looked at it, then one to swallow. The remaining piece of "paper lots" when the Church was opened: read "dead" word. This confirms Liu Yong just swallowed them goes "paper lots" is "life lots." So, when the Church Emperor Qianlong had pardoned Liu Yong.