Names with indeterminate connotation are not to be confounded with names which have more than one connotation, that is to say, ambiguous words. A word may have several meanings, but all of them fixed and recognised ones; as the word _post_, for example, or the word _box_, the various senses of which it would be endless to enumerate. And the paucity of existing names, in comparison with the demand for them, may often render it advisable and even necessary to retain a name in this multiplicity of acceptations, distinguishing these so clearly as to prevent their being confounded with one another. Such a word may be considered as two or more names, accidentally written and spoken alike.[7] § 6. The fourth principal division of names, is into _positive_ and _negative_. Positive, as _man_, _tree_, _good_; negative, as _not-man_, _not-tree_, _not-good_. To every positive concrete name, a corresponding negative one might be framed. After giving a name to any one thing, or to any plurality of things, we might create a second name which should be a name of all things whatever, except that particular thing or things. These negative names are employed whenever we have occasion to speak collectively of all things other than some thing or class of things. When the positive name is connotative, the corresponding negative name is connotative likewise; but in a peculiar way, connoting not the presence but the absence of an attribute. Thus, _not-white_ denotes all things whatever except white things; and connotes the attribute of not possessing whiteness. For the non-possession of any given attribute is also an attribute, and may receive a name as such; and thus negative concrete names may obtain negative abstract names to correspond to them. Names which are positive in form are often negative in reality, and others are really positive though their form is negative. The word _inconvenient_, for example, does not express the mere absence of convenience; it expresses a positive attribute, that of being the cause of discomfort or annoyance. So the word _unpleasant_, notwithstanding its negative form, does not connote the mere absence of pleasantness, but a less degree of what is signified by the word _painful_, which, it is hardly necessary to say, is positive. _Idle_, on the other hand, is a word which, though positive in form, expresses nothing but what would be signified either by the phrase _not working_, or by the phrase _not disposed to work_; and _sober_, either by _not drunk_ or by _not drunken_.