20. The notion of relation is the same, whether the rule any action is compared to be true or false.
Thirdly, That in
these I call moral relations, I have a true notion of relation, by comparing the action with the rule, whether the rule
be true or false. For if I measure anything by a yard, I know whether the thing I measure be longer or shorter than
that supposed yard, though perhaps the yard I measure by be not exactly the standard: which indeed is another
inquiry. For though the rule be erroneous, and I mistaken in it; yet the agreement or disagreement observable in
that which I compare with, makes me perceive the relation. Though, measuring by a wrong rule, I shall thereby be
brought to judge amiss of its moral rectitude; because I have tried it by that which is not the true rule: yet I am not
mistaken in the relation which that action bears to that rule I compare it to, which is agreement or disagreement.
