I need to know did John Stuart Mill really say this quote in his book On Liberty?

Question

"Is the encouragement of individuality, and with it the expansion of human happiness, best accomplished by an absolute prohibition against all social interference in the inner sphere of each person’s life?"

Answer 1

I cannot say - but I do know that he wrote this in the introduction to "Liberty":

"The sole end for which mankind are warranted, individually or collectively, in interfering with the liberty of action of any of their number is self-protection."

It seems to convey something of the same idea.