Ought to go on living in order to achieve what consequences? If not to achieve any consequences, then please explain precisely what you mean by “ought to go on living,” because your meaning is not obvious unless you mean to refer to consequences. Alternatively, if you mean in order to achieve consequences, the statement is consequentialist. I agree the is/ought gap can be bridged through consequentialism, but it is trivial to do so as I showed here. So I think Lilburne is looking for a non-consequentialist way to cross the is/ought divide.