In drawing attention to Clarke's system, I ought perhaps to remark that his anxiety to exhibit the parallelism between ethical and mathematical truth (on which Locke before him had insisted) renders his general terminology inappropriate, and occasionally leads him into downright extravagances. E.g. it is patently absurd to say that ``a man who wilfully acts contrary to Justice wills things to be what they are not and cannot be'': nor are ``Relations and Proportions'' or ''fitnesses and unfitnesses of things'' very suitable designations for the matter of moral intuition. But for the present purpose there is no reason to dwell on these defects.