T 2.2.12.7

Every one has observ'd how much more dogs are animated when they hunt in a pack, than when they pursue their game apart; and 'tis evident this can proceed from nothing but from sympathy. 'Tis also well known to hunters, that this effect follows in a greater degree, and even in too great a degree, where two packs, that are strangers to each other, are join'd together. We might, perhaps, be at a loss to explain this phænomenon, if we had not experience of a similar in ourselves.