The Complete Aristotle (eng.)

each is an
‘animal’. For constructive purposes, on the other hand, see if of
things that are the same in kind as the subject the property that
is the same as the alleged property is always true: for then what
is stated not to be a property will be a property. Thus (e.g.)
since it is a property of man to be a ‘walking biped,’ it would
also be a property of a bird to be a ‘flying biped’: for each of
these is the same in kind, in so far as the one pair have the
sameness of species that fall under the same genus, being under the
genus ‘animal’, while the other pair have that of differentiae of
the genus, viz. of ‘animal’. This commonplace rule is deceptive
whenever one of the properties mentioned belongs to some one
species only while the other belongs to many, as does ‘walking
quadruped’.
    Inasmuch as ‘same’ and ‘different’ are terms used in several
senses, it is a job to render to a sophistical questioner a
property that belongs to one thing and that only. For an attribute
that belongs to something qualified by an accident will also belong
to the accident taken along with the subject which it qualifies;
e.g. an attribute that belongs to ‘man’ will belong also to ‘white
man’, if there be a white man, and one that belongs to ‘white man’
will belong also to ‘man’. One might, then, bring captious
criticism against the majority of properties, by representing the
subject as being one thing in itself, and another thing when
combined with its accident, saying, for example, that ‘man’ is one
thing, and white man’ another, and moreover by representing as
different a certain state and what is called after that state. For
an attribute that belongs to the state will belong also to what is
called after that state, and one that belongs to what is called
after a state will belong also to the state: e.g. inasmuch as the
condition of the scientist is called after his science, it could
not be a property of ‘science’ that it is ‘incontrovertible by
argument’; for then the scientist also will be incontrovertible by
argument. For constructive purposes, however, you should say that
the subject of an accident is not absolutely different from the
accident taken along with its subject; though it is called
‘another’ thing because the mode of being of the two is different:
for it is not the same thing for a man to be a man and for a white
man to be a white man. Moreover, you should take a look along at
the inflections, and say that the description of the man of science
is wrong: one should say not ‘it’ but ‘he is incontrovertible by
argument’; while the description of Science is wrong too: one
should say not ‘it’ but ‘she is incontrovertible by argument’. For
against an objector who sticks at nothing the defence should stick
at nothing.
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5
    Next, for destructive purposes, see if, while intending to
render an attribute that naturally belongs, he states it in his
language in such a way as to indicate one that invariably belongs:
for then it would be generally agreed that what has been stated to
be a property is upset. Thus (e.g.) the man who has said that
‘biped’ is a property of man intends to render the attribute that
naturally belongs, but his expression actually indicates one that
invariably belongs: accordingly, ‘biped’ could not be a property of
man: for not every man is possessed of two feet. For constructive
purposes, on the other hand, see if he intends to render the
property that naturally belongs, and indicates it in that way in
his language: for then the property will not be upset in this
respect. Thus (e.g.) he who renders as a property of ‘man’ the
phrase ‘an animal capable of receiving knowledge’ both intends, and
by his language indicates, the property that belongs by nature, and
so ‘an animal capable of receiving knowledge’ would not be upset or
shown in that respect not to be a property of man.
    Moreover, as regards all the things that are called as they are
primarily after something else, or primarily in themselves, it is a
job to render the property of such things. For if you render a
property as belonging to the subject that is so called after
something else, then it will be true of its primary subject as
well; whereas if you state it of its primary subject, then it will
be predicated also of the thing that is so called after this other.
Thus (e.g.) if any one renders ,