It can be commonly said that two emphases for designers are aesthetics and purposiveness. These are, in other words, the sense of beauty which you may have when you encounter an object and the importance of the function acquired from the object. On the other hand, for Kant, the pure aesthetic judgement of taste is not to presuppose an end. But we experience pleasure to well-designed objects which include their purposes, even though they are not works of fine arts, At the very same idea, on the beauty of objects that we recognize as having intended ends or functions, Kant forges the very unique concept ‘adherent beauty (pulchritudo adhaerens)’.
By the way, In fact, the concept of adherent beauty is not only revealed in Kant but also in the early Greek aesthetics. The beauty fitted for its purpose is named ‘harmotton’ by Socrates, later it is called ‘prepon’ by Greeks. Afterward, this terminology is translated ‘decorum’ or ‘aptum’ in Latin, and thus there are two types of beauty, pulchrum and decorum in those days. That is, there is a beautiful object caused by its practicality or suitability in distinction from an object beautiful in itself.
The theory of functionalism that the beauty relies on an object’s purposiveness and suitability was formerly adopted by Socrates, and later appeared in the theory of decorum deliberately and consistently by periods, and thus, it had become the general principle of design in the latter half of the 19th century and the 20th century. In the meantime, the consistency of the idea related with purposiveness or suitability can be seen from Henry Home prior to the concept of adherent beauty by Kant. In his main work, Elements of criticism(1762), Home distinguishes intrinsic beauty from relative beauty, which are linked to free beauty(pulchritudo vaga) and adherent beauty(pulchritudo adhaerens) in Kant.
Kant mentions initially the concept of adherent beauty in §16 in his Critique of the Power of Judgment. From Kant’s statements, we could grasp certain points: firstly, he starts with that adherent beauty presupposes a “concept of what th object should be” and “the perfection of the object in accordance with it”(KdU, §16, 48); secondly, however, he characterizes adherent beauty as “conditioned beauty”, and he also a little later on mentions that the supposed concept in case of adherent beauty is one “by which the imagination, which is as it were at play in the observation of the shape, would merely be restricted”(KdU, §16, 50). But it turns out that this restriction functions as a necessary condition; lastly, Kant alludes that in adherent beauty, there is a combination of independent pleasures, a pleasure in the pure beauty of the object on the one hand and a pleasure in its goodness or perfection in accordance with a certain end on the other hand.
Putting together all statements of Kant which referred to adherent beauty in relation to form and function, objects which bear certain purposes and functions could be all products designed and produced by human, and the desire toward those design products could be a motive power for the development of culture and civilization. Furthermore, and then, the fact that in the case of adherent beauty conditions for functionality of any object can play an essential role as a necessary condition for our pleasure in its beauty could be a basis for the motto of the modern design of functionalism; “form follows function”. It is meaningful that the concept of adherent beauty which is presented in Kant's aesthetics is considered in relation with design. In addition, this consideration can be one moment extending the meaning and horizon of design, with finding the basis of beauty discovered through arts, and especially design, not just fine arts.