Not sure. I usually take it as axiomatic.
What about you? Would you limit the legislature to those laws governing behavior which harms others?
Then you'd be wrong, wouldn't you? What makes you believe that legislatures, by definition, are to limit their law making to behavior which harms others?
"Would you limit the legislature to those laws governing behavior which harms others?"
Nope. There's no need to do that. Why do you wish to limit the will of the people?