以前在网上看到的，感觉很有趣——

1.       I accidentally divided by zero and my paper burst into flames.

2.       Isaac Newton's birthday.

3.       I could only get arbitrarily close to my textbook. I couldn't actually reach it.

4.       I have the proof, but there isn't room to write it in this margin.

5.       I was watching the World Series and got tied up trying to prove that it converged.

6.       I have a solar powered calculator and it was cloudy.

7.       I locked the paper in my trunk but a four-dimensional dog got in and ate it.

8.       I couldn't figure out whether i am the square of negative one or i is the square root of negative one.

9.       I took time out to snack on a doughnut and a cup of coffee. I spent the rest of the night trying to figure which one to dunk.

10.   I could have sworn I put the homework inside a Klein bottle, but this morning I couldn't find it.

这些富有想象力的理由恐怕要做过很多数学作业以后才想得出来。于是有了一个悖论：为了想出更好的不做数学的理由，我们必须做好数学作业。