The existing perfeies are said existing in Act. The perfeies that can come to exist in a citizen are existing in passive Power. Thus, a white wall has brancura in Act, but it has red color in Power. Change or movement is therefore the ticket of power of a perfection any (x) for the ownership of that perfection in Act. M = PX —- AX Nothing can pass, alone, of power for a perfection, the Act of that one same perfection.
To move, it needs the aid of another being that has that quality in Act. Thus, the pan can be warm. But it is not heated alone. To be heated, it needs to receive the heat from another being – the fire – that has heat in Act. Another example: The white wall in Act, red in power, will only be red in Act in case that it receives the red from another being – the ink – that is red in Act.
In other words, everything what dumb it is moved by another one. It is moved what it was in power for a perfection. In exchange, to move, to be motor, she is necessary to have the quality in act. The fire (hot in act) moves, dumb the pan (hot in power) for hot in act. However, it is impossible that a thing is, at the same time, in power and act for the same quality. Former: If the pan is cold in act, it has power to be warm. If the pan is hot in act it does not have power to be warm. It is therefore impossible that a thing is motor and mobile, at the same time, for the same perfection. It is impossible, therefore, that a thing changes same itself. Everything what dumb it is moved by another one. Everything what is moved is moved by another one.