The _Aesthetic_ opens with a series of definitions. =Intuition= (_Anschauung_) is knowledge (_Erkenntnis_) which is in immediate relation to objects (_sich auf Gegenstände unmittelbar bezieht_). Each term in this definition calls for comment. _Anschauung_ etymologically applies only to visual sensation. Kant extends it to cover sensations of all the senses. The current term was _Empfindung_. Kant’s reason for introducing the term intuition in place of sensation was evidently the fact that the latter could not be made to cover space and time. We can speak of pure intuitions, but not of pure sensations. _Knowledge_ is used in a very wide sense, not strictly consistent with A 50-1 = B 74-5.[345] The phrase _sich bezieht_ is quite indefinite and ambiguous. Its meaning will depend upon the interpretation of its context. _Object_ is used in its widest and most indefinite meaning. It may be taken as signifying content (_Inhalt_, a term which does not occur in this passage, but which Kant elsewhere employs[346]). That, at least, is the meaning which best fits the context. For when Kant adds that intuition relates itself to objects _immediately_, it becomes clear that he has in mind its distinction from conception (_Begriff_) which as expressing the universal is related to objects only indirectly, representing some one or more attributes of the _given_ objects. Ultimately the whole content of conception must be given.[347] The phrase “relates itself to objects” may, therefore, be paraphrased “has some content, such as red or cold, as its immediate object.” Through the content of intuition the whole material of thought is supplied. Intuition in itself is blind, but not empty. “Thoughts without content are empty; intuitions without concepts are blind.”[348] But the phrase “is in relation to objects” has also for Kant a second meaning, implied in the above, but supplementary to it. As he states in the very next sentence, intuition can have an object, meaning thereby a content, only in so far as that content is _given_. The material of thought must be supplied; it cannot be invented.[349] The only mode, however, in which it can be supplied, at least to the human mind, is through the affecting of the mind by “the object.” This is an excellent instance of Kant’s careless mode of expressing himself. In the first part of the sentence object means _object of intuition_. In the latter part it signifies the _cause of intuition_. And on Kant’s view the two cannot coincide. The object which affects the mind is independently real; the immediate object of the intuition is a sense-content, which Kant, following the universally accepted view of his time, regards as purely subjective. The term object is thus used in two quite distinct meanings within one and the same sentence.