Nay, we may go further, and say that it is practically plain what among things which can be otherwise does exist by nature, and what does not but is dependent upon enactment and conventional, even granting that both are alike subject to be changed: and the same distinctive illustration will apply to this and other cases; the right hand is naturally the stronger, still some men may become equally strong in both. A parallel may be drawn between the Justs which depend upon convention and expedience, and measures; for wine and corn measures are not equal in all places, but where men buy they are large, and where these same sell again they are smaller: well, in like manner the Justs which are not natural, but of human invention, are not everywhere the same, for not even the forms of government are, and yet there is one only which by nature would be best in all places. Chapter XI. Now of Justs and Lawfuls each bears to the acts which embody and exemplify it the relation of an universal to a particular; the acts being many, but each of the principles only singular because each is an universal. And so there is a difference between an unjust act and the abstract Unjust, and the just act and the abstract Just: I mean, a thing is unjust in itself, by nature or by ordinance; well, when this has been embodied in act, there is an unjust act, but not till then, only some unjust thing.[24] And similarly of a just act. (Perhaps δικαιοπράγημα is more correctly the common or generic term for just act, the word δικαίωμα, which I have here used, meaning generally and properly the act corrective of the unjust act.) Now as to each of them, what kinds there are, and how many, and what is their object-matter, we must examine afterwards. For the present we proceed to say that, the Justs and the Unjusts being what have been mentioned, a man is said to act unjustly or justly when he embodies these abstracts in voluntary actions, but when in involuntary, then he neither acts unjustly or justly except accidentally; I mean that the being just or unjust is really only accidental to the agents in such cases. So both unjust and just actions are limited by the being voluntary or the contrary: for when an embodying of the Unjust is voluntary, then it is blamed and is at the same time also an unjust action: but, if voluntariness does not attach, there will be a thing which is in itself unjust but not yet an unjust action.