From a friend:

"I had to look up "paraprosdokian". Here is the definition : "Figure of speech in which the latter part of a sentence or phrase is surprising or unexpected; frequently used in a humorous situation."
"Where there's a will, I want to be in it," is a type of paraprosdokian.

A choice of examples:

1. Do not argue with an idiot. He will drag you down to his level and beat you with experience.
2. The last thing I want to do is hurt you. But it's still on my list.
3. Light travels faster than sound. This is why some people appear bright until you hear them speak.
4. If I agreed with you, we'd both be wrong.
5.. War does not determine who is right - only who is left.
6. Knowledge is knowing a tomato is a fruit. Wisdom is not putting it in a fruit salad.
7. To steal ideas from one person is plagiarism. To steal from many is research."

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