Function is not as trivial as some might think. In the modern world where machines essentially think and are programmable, new functions can be invented and programmed into being, even though the original designers of the hardware had no idea this function might be served some day. Does this mean that function is no longer useful as a design parameter? No, not at all. What it means is that picking out important functions has gotten less obvious.

There is a principle in technical definitions that must be kept in mind. The purpose of definitions is to be useful in the work that is being done by describing a unique concept. It does little good to make sweeping definitions that are politically correct by including everything but pin down nothing. For example, many groups have tried to redefine the English word “violence” to mean all kinds of new oppressions beyond the traditional physical violence. These new definitions may allow new actions to be denigrated using the negative connotations of physical violence but the base word suffers in being diluted. Similarly with “racism”. Political adoptions like these may be politically useful but they muddle the ability to know what one is referring to in any kind of analytic discussion. Unlike Humpty Dumpty’s dictum, words cannot mean whatever I say they mean and still be useful.

 In the instant case, where redesign is being urged for the purpose of making better use of resources used to make products, the sub-functions which may be invented by programming are not designed for up front and therefore are not the ones covered by the word redesign. What is essential is the design of physical resources in making the hardware. If the hardware itself can be designed with subcomponents that can be replaced and attached together, for example (modularization) then that is an innovation that is needed no matter what subfunction those modules are going to be used for. It is in the nature of programming to be repairable and modularized (though this can’t be taken for granted).

On the other hand, applying a subfunction (let’s say, using a computer to control a cutting machine) is itself a design problem and can be done conservatively or wastefully. Each function, at any level, needs to be designed intelligently.

Here are two imaginative treatments of function. The first is medical and concerns the functions of the human brain. The second imagines that the functions of words create language.

The human brain presents a puzzling and challenging paradox. Despite a fixed anatomy, characterized by its connectivity, its functional repertoire is vast, enabling action, perception and cognition. This contrasts with organs like the heart that have a dynamic anatomy but just one function. The resolution of this paradox may reside in the brain’s network architecture which organizes local interactions to cope with diverse environmental demands – ensuring adaptability, robustness, resilience to damage, efficient message passing and diverse functionality from a fixed structure. This review asks how recent advances in understanding brain networks elucidate the brain’s many-to-one (degenerate) function-structure relationships. In other words, how does diverse function arise from an apparently static neuronal architecture? We conclude that the emergence of dynamic functional connectivity from static structural connections, calls for formal (computational) approaches to neuronal information processing that may resolve the dialectic between structure and function.   From Science magazine, Vol. 342, Nov 1, 2013, p. 579

 And now for a discussion of the function of words in language.

Yes. A language that will at last say what we have to say. For our words no longer correspond to the world. When things were whole, we felt confident that our words could express them. But little by little, these things have been broken apart, shattered, collapsed into chaos. And yet our worlds have remained the same. They have not adapted themselves to the new reality. Hence, every time we try to speak of what we see, we speak falsely, distorting the very thing we are trying to represent. It’s made a mess of everything. But words, as you yourself understand, are capable of change. The problem is how to demonstrate this. That is why I now work with the simplest means possible – so simple that even a child can grasp what I am saying. Consider a word that refers to a thing – ‘umbrella’ for example. When I say the word ‘umbrella’, you see the object in your mind. You see a kind of stick, with collapsible metal spokes on top that form an armature for a waterproof material which, when opened, will protect you from the rain. This last detail is important. Not only is an umbrella thing, it is a thing that performs a function – in other words, expresses the will of man. When you stop to think of it, every object is similar to the umbrella, in that it serves a function. A pencil is for writing, a shoe is for wearing, a car is for driving. Now, my question is this. What happens when a thing no longer performs its function? Is it still the thing or has it become something else? When you rip the cloth off the umbrella, is the umbrella still the umbrella? You open the spokes, put them over your head, walk out into the rain, and you get drenched. Is it possible to go on calling this object an umbrella? In general, people do. At the very limit, they will say the umbrella is broken. To me, this is a serious error, the source of all our troubles. Because it can no longer perform its function, the umbrella has ceased to be an umbrella. It might resemble an umbrella. It might once have been an umbrella but now it has changed into something else. The word however has remained the same. Therefore it can no longer express the thing. It is imprecise, it is false, it hides the thing it is supposed to reveal. And if we cannot even name a common everyday object that we hold in our hands, how can we expect to speak of the things that truly concern us. Unless we begin to embody the notion of change in the words we use, we will continue to be lost.

From: City of Glass, by Paul Auster, pp 121-2 (1987)