Immanuel Kant's Critique of Pure Reason — trans. F. Max Müller

584 Discipline of Pure Reason philosophy to teach the limits of knowledge, and even the mathematician, unless his talent is limited already by nature and restricted to its proper work, cannot decline the warnings of philosophy or altogether defy them.

I. Of Definitions. To define, as the very name implies, means only to represent the complete concept of a thing within its limits and in its primary character.^ From this point of view, an empirical concept cannot be defined, but can be explained only. For, as we have in an empirical concept some predicates only belonging to a certain class of sensuous objects, we are never certain whether by the word which denotes one and the same object, we do not think at one time a greater, at another a smaller number of predicates. Thus one man may by the [p. 728] concept of gold think, in addition to weight, colour, malleability, the quality of its not rusting, while another may know nothing of the last. We use certain predicates so long only as they are required for distinction. New observations add and remove certain predicates, so that the concept never stands within safe limits. And of what use would it be to define an empirical concept, as for instance that of water, because, when we speak of water and its qualities, we do not care much what is thought by that word, but proceed at once to experiments } the word itself with its few predicates being a designation only and not a concept, so that a so-called definition would be no more

1 Completeness means clearness and sufficiency of predicates; limits mean precision, no more predicates being given than belong to the complete concept; in its primary character means that the determination of these limits is not derived from anything else, and therefore in need of any proof, because this would render the so-called definition incapable of standing at the head of all the judgments regarding its object.

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than a determination of the word. Secondly, if we reasoned accurately, no a priori given concept can be defined, such as substance, cause, right, equity, etc. For I can never be sure that the clear representation of a given but still confused concept has been completely analysed, unless I know that such representation is adequate to the object.

As its concept, however, such as it is given, may contain many obscure representations which we pass by in our analysis, although we use them always in the practical application of the concept, the completeness of the analysis of my concept must always remain doubtful, and can only be rendered probable by means of apt examples, although never apodictically certain.

I should [p. 729] therefore prefer to use the term exposition rather than definition, as being more modest, and more likely to be admitted to a certain extent by a critic who reserves his doubts as to its completeness. As therefore it is impossible to define either empirically or a prio7d given concepts, there remain arbitrary concepts only on which such an experiment may be tried.

In such a case I can always define my concept, because I ought certainly to know what I wish to think, the concept being made intentionally by myself, and not given to me either by the nature of the understanding or by experience. But I can never say that I have thus defined a real object.

For if the concept depends on empirical conditions, as, for instance, a ship's chronometer, the object itself and its possibility are not given by this arbitrary concept ; it does not even tell us whether there is an object corresponding to it, so that my explanation should be called a declaration (of my project) rather than a definition of an object. Thus there remain no concepts fit for definition except those which contain