Plotinos: Complete Works, v. 3 In Chronological Order,...

2. After denying that sensation consists of such an operation, it is our duty to point out the true state of affairs. Though it be objected that thus the soul would be considered as judging of things she does not possess, it is nevertheless plain that it is the characteristic of a power, not to experience or suffer, but to develop its force, to carry out the function to which it is destined. If the soul is to discern a visible or audible object the latter must consist of neither images nor experiences, but actualizations relative to the objects which naturally belong to the domain of these actualizations of the soul. Those who deny that any faculty can know its object without receiving some impulsion from it imply that the faculty suffers, without really cognizing the object before it; for this soul-faculty should dominate the object instead of being thereby dominated.