Theories of Technical Functions: Function Ascriptions Versus Function Assignments, Part 1

Introduction The notion of function plays a central role in the engineer’s way of thinking. It is hard to imagine how engineers could do without function talk.2 They assume that the technical artifacts they design, make, and maintain and their components all have technical functions. But what does it mean to say that a technical artifact “has” a technical function (or a functional property or feature)? This question has been troubling engineers as well as philosophers. Engineers address this problem mainly for pragmatic reasons; they are interested in knowing how to represent formally or computationally the functional properties of technical artifacts in software tools intended to support engineers in their daily work. One of the main reasons why philosophers have been interested in the notion of function is its connection with the notion of teleology, which itself raises all kinds of conceptual, metaphysical, and epistemological problems. A problem that both engineers and philosophers run into when analyzing the notion of technical function is its relation to physical structures and human intentions. They run into this problem from, so to speak, opposite directions. From an engineering point of view, that the function of a technical artifact, such as a television set, is closely related to its physical structure is obvious, because it is the physical structure that realizes or performs the function. One of the main tasks of engineers is to design, develop, and produce physical structures that can perform all kinds of technical functions. Nevertheless, the function of a television appears to be related also to what people use it for—that is, to the intentions of human beings. A television is a means to a certain end, and that end is an end of human beings. It is in relation to human ends only that the television appears to be a means, and to have a function. In engineering practice this close relation of technical functions to human ends comes to the fore in, for instance, the early stages of design projects, in which human needs and desires have to be translated into functions and functional requirements. Within philosophical circles the dominant starting point for analyzing technical functions is the idea that these functions are mind dependent; technical artifacts are taken to have their functions only in