a certain time, we observe as to the present time, wherefore there are not many arguments belonging to it, but that is a logical problem, in reference to which numerous and good arguments may be framed.
What therefore is stated to be property with reference to something else, must be considered from the places concerning accident, viz. whether it happens to one, but not to another, but those which are at all times, and per se, we must examine by the following places.
Chapter 2
First, (it must be considered) whether property be not well or be well explained; of the ill or well, one point indeed is, if the property is laid down, not through things which are more known, or which are more known; subverting it, if not through things more known, but confirming it if through things more known. Now of the (being laid down), not through things more known, one (place) is, if the property which a person assigns, is altogether more unknown, than that of which he states it to be the property, for the property will not be well laid down. For we introduce property for the sake of knowledge, wherefore it should be assigned through things more known, for thus it will be more possible sufficiently to apprehend it. For instance, since he who lays it down as the property of fire to be most similar to the soul, employs the soul, which is more unknown than fire, (for we know more what fire, than what the soul, is,) it would not be well laid down as the property of fire to be most similar to the soul. Another (way) is, if it is not more known that this is present with that, since it is necessary not only that (the property) should be more known than the thing, but also that it should be more known to be present with this thing, since he who is ignorant, whether it is present with this thing, will not know whether it is present with this alone, so that whatever of these happens to be the case, the property becomes obscure. For instance, since he who lays down the property of fire, to
