In other words, to teach people to feel pleasure when they feel nothing because feeling nothing is missed opportunity due to our misjudgement of reality we find ourselves in.
I generally agree with Tau Phi's post except perhaps for this sentence wording here. "When they feel nothing" probably ought to be made more clear as something like "when they are not feeling sensually stimulated.". The rejection of a neutral state is probably inconsistent with the flatness of "when they feel nothing." The explicit statement is that you are always feeling one of the two, pleasure or pain, so there is never a time when you flatly "feel nothing" except when you are unconscious.