General words do not signify a single particular nor a mere plurality, but a 'sort of things'; each general term does this by standing for an abstract idea, and these abstract ideas are precisely the essences of genera and species—what makes anything to be of a given sort.

By John Locke, from An Essay Concerning Human Understanding

Key Arguments

  • Locke distinguishes general from proper names by their signification: 'as it is evident that they do not signify barely one particular thing; for then they would not be general terms, but proper names, so, on the other side, it is as evident they do not signify a plurality; for man and men would then signify the same'.
  • He concludes: 'That then which general words signify is a sort of things; and each of them does that, by being a sign of an abstract idea in the mind; to which idea, as things existing are found to agree, so they come to be ranked under that name, or, which is all one, be of that sort.'
  • From this he infers that 'the essences of the sorts, or, if the Latin word pleases better, species of things, are nothing else but these abstract ideas', because 'having the essence of any species' is 'that which makes anything to be of that species', and that is precisely conformity to the abstract idea the general word stands for.
  • Thus the 'essence' that constitutes species membership is not some hidden real nature in things but the abstract idea serving as the nominal essence, fixed by the mind and language.

Source Quotes

The next thing therefore to be considered is, What kind of signification it is that general words have. For, as it is evident that they do not signify barely one particular thing; for then they would not be general terms, but proper names, so, on the other side, it is as evident they do not signify a plurality; for man and men would then signify the same; and the distinction of numbers (as the grammarians call them) would be superfluous and useless. That then which general words signify is a sort of things; and each of them does that, by being a sign of an abstract idea in the mind; to which idea, as things existing are found to agree, so they come to be ranked under that name, or, which is all one, be of that sort.
For, as it is evident that they do not signify barely one particular thing; for then they would not be general terms, but proper names, so, on the other side, it is as evident they do not signify a plurality; for man and men would then signify the same; and the distinction of numbers (as the grammarians call them) would be superfluous and useless. That then which general words signify is a sort of things; and each of them does that, by being a sign of an abstract idea in the mind; to which idea, as things existing are found to agree, so they come to be ranked under that name, or, which is all one, be of that sort. Whereby it is evident that the essences of the sorts, or, if the Latin word pleases better, species of things, are nothing else but these abstract ideas.
That then which general words signify is a sort of things; and each of them does that, by being a sign of an abstract idea in the mind; to which idea, as things existing are found to agree, so they come to be ranked under that name, or, which is all one, be of that sort. Whereby it is evident that the essences of the sorts, or, if the Latin word pleases better, species of things, are nothing else but these abstract ideas. For the having the essence of any species, being that which makes anything to be of that species; and the conformity to the idea to
Whereby it is evident that the essences of the sorts, or, if the Latin word pleases better, species of things, are nothing else but these abstract ideas. For the having the essence of any species, being that which makes anything to be of that species; and the conformity to the idea to

Key Concepts

  • For, as it is evident that they do not signify barely one particular thing; for then they would not be general terms, but proper names, so, on the other side, it is as evident they do not signify a plurality; for man and men would then signify the same; and the distinction of numbers (as the grammarians call them) would be superfluous and useless
  • That then which general words signify is a sort of things; and each of them does that, by being a sign of an abstract idea in the mind; to which idea, as things existing are found to agree, so they come to be ranked under that name, or, which is all one, be of that sort
  • Whereby it is evident that the essences of the sorts, or, if the Latin word pleases better, species of things, are nothing else but these abstract ideas
  • For the having the essence of any species, being that which makes anything to be of that species; and the conformity to the idea to

Context

Book III, Chapter III, §12 (as far as quoted), where Locke clarifies the signification of general words and identifies abstract ideas as the essences of genera and species (their nominal essences).