 It can never in the least concern us to know, that such objects are causes, and such others effects, if both the causes and effects are indifferent to us. Where the objects themselves do not affect us, their connexion can never give them any influence; and ‘tis plain, that as reason is nothing but the discovery of this connexion, it cannot be by its means that the objects are able to affect us (T 2.3.3.3/414).