complex ideas be not always copied from nature, yet they are always
suited to the end for which abstract ideas are made: and though they be
combinations made of ideas that are loose enough, and have as little
union in themselves as several other to which the mind never gives a
connexion that combines them into one idea; yet they are always made for
the convenience of communication, which is the chief end of language.
The use of language is, by short sounds, to signify with ease and
dispatch general conceptions; wherein not only abundance of particulars
may be contained, but also a great variety of independent ideas
collected into one complex one. In the making therefore of the species
of mixed modes, men have had regard only to such combinations as they
had occasion to mention one to another. Those they have combined into
distinct complex ideas, and given names to; whilst others, that in
nature have as near a union, are left loose and unregarded. For, to go
no further than human actions themselves, if they would make distinct
abstract ideas of all the varieties which might be observed in them, the
number must be infinite, and the memory confounded with the plenty, as
well as overcharged to little purpose. It suffices that men make and
name so many complex ideas of these mixed modes as they find they have
occasion to have names for, in the ordinary occurrence of their affairs.
If they join to the idea of killing the idea of father or mother, and
so make a distinct species from killing a man's son or neighbour, it
is because of the different heinousness of the crime, and the distinct
punishment is due to the murdering a man's father and mother, different
to what ought to be inflicted on the murder of a son or neighbour; and
therefore they find it necessary to mention it by a distinct name, which
is the end of making that distinct combination. But though the ideas of
mother and daughter are so differently treated, in reference to the idea
of killing, that the one is joined with it to make a distinct abstract
idea with a name, and so a distinct species, and the other not; yet, in