Logical deduction 逻辑推理
The teacher asked her students in class: "If there are five flies on your desk and you kill one, how many will remain?"
"One," shouted a boy, "the dead one." The teacher said: "You should know that there are still four not dead."
The boy replied: "I know, but they have flown away."
He is right. Arithmatic is one thing, but logic is another.
上课时老师问学生：“如果有5只苍蝇在你的书桌上，你打死了一只，还剩下多少只？”
“一只，就是死了的那只。”一个男孩大声回答道。老师说：“你应该知道还有4只没有死嘛。
男孩回答说：“我知道，可是它们已经飞走了。
他是对的，算术是一回事，而逻辑是另一回事。