Note 58 — Chapter III · * OTHER COMPANIONS OF SOKRATES.

Hobbes, in his Computation or Logic (chaps. ix. and x. Of Cause and Effect. Of Power and Act) expounds this subject with his usual perspicuity.

“A Cause simply, or an Entire Cause, is the aggregate of all the accidents, both of the agents, how many soever they be, and of the patient, put together; which, when they are all supposed to be present, it cannot be understood but that the effect is produced at the same instant: and if any one of them be wanting, it cannot be understood but that the effect is not produced” (ix. 3).

“Correspondent to Cause and Effect are Power and Act: nay, those and these are the same things, though for divers considerations they have divers names. For whensoever any agent has all those accidents which are necessarily requisite for the production of some effect in the patient, then we say that agent has power to produce that effect if it be applied to a patient. In like manner, whensoever any patient has all those accidents which it is requisite it should have for the production of some effect in it, we say it is in the power of that patient to produce that effect if it be applied to a fitting agent. Power, active and passive, are parts only of plenary and entire power: nor, except they be joined, can any effect proceed from them. And therefore these powers are but conditional: namely, the agent has power if it be applied to a patient, and the patient has power if it be applied to an agent. Otherwise neither of them have power, nor can the accidents which are in them severally be properly called powers: nor any action be said to be possible for the power of the agent alone or the patient alone.”