The first proper significate effect of a sign is a feeling produced by it. There is almost always a feeling which we come to interpret as evidence that we comprehend the proper effect of the sign, although the foundation of truth in this is frequently very slight. This “emotional interpretant,” as I call it, may amount to much more than that feeling of recognition; and in some cases, it is the only proper significate effect that the sign produces. Thus, the performance of a piece of concerted music is a sign. It conveys, and is intended to convey, the composer’s musical ideas; but these usually consist merely in a series of feelings. If a sign produces any further proper significate effect, it will do so through the mediation of the emotional interpretant, and such further effect will always involve an effort.
…there are three different interpretants. First, there is the “emotional interpretant,” which consists in a feeling, or rather in the quality of a feeling. A concerted piece of music, for example, brings a succession of musical emotions answering to those of the composer. This is an extreme case; usually the emotional interpretant consists merely in a sense, more or less complex, perhaps amounting to an image, perhaps not, of the meaning of the sign. All signs whatsoever must, in order to fulfill their functions as signs, first of all produce such emotional interpretants. [—] The emotional interpretant, immediately produced by the sign, corresponds to the immediate object.
It is now necessary to point out that there are three kinds of interpretants. Our categories suggest them, and the suggestion is confirmed by careful examination. I terms them the Emotional, the Energetic, and Logical Interpretants. They consist respectively in feelings, in efforts, and in habit-changes. [—]
Every sign whatever that functions as such must have an emotional interpretant; for under that head comes the feeling of recognizing the sign as such; and it is plain that a sign not recognized is not a sign at all. The performance of a piece of music may excite musical emotions without being a sign. But if the hearer discerns in the notes the musical ideas or emotions of a composer, then the music conveys a message from the composer, and it becomes a sign.