Why do men and women differ?

[xyz]

Now I know why men and women differ...
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An English professor wrote the words, \"Woman without her man is nothing\" on the blackboard and directed his students to punctuate it correctly.
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The men wrote: \"Woman, without her man, is nothing.\"
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The women wrote: \"Woman: Without her, man is nothing.\"

[Kulcha Hyderabadi]

I think they differ in more than many ways - besides punctuation!