Supuestos de concurrencia de convenios en relación con el Convenio de La Haya de 1970

opposed to engineering practice. The designing and developing of technical artefacts is often, in fact, precisely all about ‘wrestling’ between what is possible and what is desirable. In that struggle, as we shall argue in the next section, both physical-technical and social factors enter into the arena to play their part.

6.4 THE ROLE OF PHYSICAL-TECHNICAL AND SOCIAL FACTORS IN DESIGNING

It is during the design process that a technical artefact is given its concrete form. Changes in technical artefacts in relation to earlier variants are made at that point. When, as in the case of the bicycle, one wants to analyse the factors that play a part in these changes, then it would seem that the design process is the right place for doing that. In this section, we therefore present a schematic framework for analysing the role of physical-technical and social factors in the design process, and thus for analysing changes in the characteristics of technical artefacts [Kroes, P.,1996]. Changes in technical artefacts that occur during production processes and in their social implementation will not be considered here.

In Chapter2, the core of the design process was described as the establishing of a description of the physical structure of an artefact that can fulfil a given function. The function of the device that is to be designed is normally laid down in a list of functional requirements, which are then converted into a list of specifications or a programme of requirements. That function does not just come out of the blue, it is the result of social negotiation processes in which the various groups involved, including customers but also producers, articulate their wishes and needs. The function of the product that is to be developed is thus a social construction that is based upon what divergent groups consider to be ‘desirable’. The aim of the design process is to come up with a description of a physical construction that meets the conditions included in the programme of requirements.

However, not everything that is desirable is also possible, and there can be various reasons for that. The programme of requirements can contain logically contradictory demands: a design parameter like, for example, the weight must be both bigger and smaller than a certain value x. It can also be the case that the programme of requirements conflicts with what is physically possible:

for example, information has to be sent at a speed faster than the speed of light. The programme of requirements might also be technically impossible to realise, either because of the technical recourses available to the organisation where the design process is taking place or because of the general level of technology at that particular stage: e.g., there should be millions of electrical connections on a microchip with a diameter of 1 nanometre. It might finally be impossible to meet the programme of requirements because of social, economic or cultural constraints: for instance, in connection with safety requirements, the cost price that has been fixed or due to moral constraining factors. The most interesting case for the analysis of the role of physical-technical and social factors in designing is the case in which a programme of requirements cannot be executed because of the technological level in

general. In that situation, the technical preconditions are such that a design that satisfies the whole list of specifications is technically not realisable.

To sum up, both what is desirable and what is possible result in constraints or boundary conditions on the artefact that is to be designed. Together, they determine the solution space for the design problem. As long as no conflict arises between what is desirable and what is possible, it is down to the ingenuity of the designer to think up a solution. When such a conflict does arise, the solution space will, in principle, be empty. What can be done in such a case? That all depends on the nature of the conflict. When a conflict arises between what is desirable and what is physically possible, then the only option would seem to be to redefine what is desirable in the programme of requirements. In the case of a conflict with technical preconditions, that is also a fairly obvious option, but what one can then also do is to try to change the technical preconditions by moving the boundaries of the ‘state of the art’ in technology; that can be done by means of starting physical-technical research programmes. The last solution is, of course, only a sensible one if there is a real chance that the limits of what is technologically possible can be changed in such a way that the programme of requirements can ultimately be realised. Whenever there is evidence of a conflict with social, economic or cultural constraints, one can, in principle, try to adjust these constraints by means of social processes of negotiation. Again that would only seem to be a clever option when there is a reasonably chance of success. In cases when such constraints are related to fundamental norms and values in society, then it is very difficult to alter those constraints.

If one represents the artefact that is to be designed as a black box (see Figures1.2and2.1) which, at a given input, is expected to produce a corresponding output, then the whole collection of boundary conditions concerning what is desirable and what is possible can be divided up into two sub collections:

The physical-technical boundary conditions.

The physical and technical boundary conditions have their origin in and are derived from the content or future content of the black box. Whichever physical construction is proposed as a solution, it will in any case have to meet the requirement that it is physically possible. But not everything that is physically possible is, at a certain time, also technically possible. That is why the content of the black box will have to meet the requirement that it is technically possible to construct the content thereof.

The contextual boundary conditions.

What falls into the contextual boundary conditions category is all the other conditions.

We call those conditions contextual because they have their origins in and are derived from the context of the artefact that is to be designed, in which the user’s context plays an important part.

One of the most challenging aspects of technical designing and the driving force behind the de-velopment of new technical artefacts is the tension which exists between both types of boundary conditions, between what a technical artefact is capable of doing on the basis of what at a given

6.4. THE ROLE OF PHYSICAL-TECHNICAL AND SOCIAL FACTORS IN DESIGNING 97 moment in time is technologically possible and the requirements placed upon that technical artefact by the environment (see Figure6.7).

Physical-Technical Boundary Conditions

Technical Artefact

Contextual Boundary Conditions

Figure 6.7: The tension between physical-technical and contextual boundary conditions.

If one takes a closer look at the collection of contextual boundary conditions, then one can observe that they have a very heterogeneous character. They include requirements with respect to the following:

• the primary function of the technical artefact

• the use (safety, user-friendliness, climatological and geographical conditions, et cetera)

• production (safe to produce, mass production possibilities, preconditions derived from pro-duction facilities, et cetera)

• maintenance (safety, costs, et cetera)

• market (price)

• insurance

• financing

• legal aspects (patents)

• environment

• technical standards and norms

• aesthetic criteria

• et cetera

What lies hidden behind each of these boundary conditions are the respective interested parties (stakeholders); they can be individuals but also organisations, government bodies or social groups.

Whenever there are conflicts between the different contextual boundary conditions, it will be primarily those interested parties that will have to find the solutions (primarily, because one cannot

completely exclude the possibility that contextual conditions that might originally have been in conflict with each other, do eventually become compatible thanks to technological innovations; see the discussion on the design of jet engines and noise hindrance in Section3.4). This would indicate that such contextual boundary conditions are in principle negotiable. They are socially constructed in the sense that they are the outcomes of complicated negotiation processes between the various interested parties (this does not mean to say that these negotiation processes can always be controlled;

see the discussion on the emergent properties of sociotechnical systems that is given in Chapter5 and at the end of this chapter). In that respect, it may be said that contextual conditions are essentially different from physical-technical preconditions. Physical boundary conditions are not negotiable on the basis of the interests of the parties concerned. Uncertainties can obviously arise in relation to the validity of physical conditions but such uncertainty can only be dispelled by research, not through negotiations in which various interests are weighed up against each other. We therefore reject the hypothesis put forward by the social constructivists to the effect that in research, physical facts are socially construed. In the case of the technical preconditions, similar considerations might be said to apply. Technological preconditions are not, in principle, negotiable. Whenever there is disagreement about the matter of whether a thing is technologically possible, technological-scientific research will have to provide the answers and not negotiation because in the latter case the outcomes are determined by the interests and positions of power of the parties involved.

There is, therefore, an important discrepancy with regard to the flexibility (negotiability) of physical-technical and contextual boundary conditions. Roughly speaking, it is a difference that can be interpreted as follows. Physical boundary conditions are factual assertions about nature; they have their origins in physically necessary relations. They are bare facts in the sense that they cannot be negotiated; they are ‘transcendent’ boundary conditions in the sense that they lie beyond any human control. Technological preconditions are also factual statements, but they have more of a contingent character: they express what in a given historical situation is de facto impossible. Constant endeavours are being made to deliberately change the boundaries of what is technologically possible by means of technological research. Those boundaries are not, however, negotiable in the sense that the outcome of the research is determined by the choices of social groups. Finally, there are contextual boundary conditions, which can have both a normative and a factual character. Contextual boundary conditions that have their origins in the desires and needs of interest groups are of a normative character; they are negotiable. If they have their origins in what in a given social situation is possible, then they have a factual character. Insofar as that social situation can, in principle, change (i.e., can be renegotiated), these contextual boundary conditions will likewise be negotiable and flexible. In a certain situation, it is thus possible that in practical terms a contextual condition, like a maximum cost price dictated by the free market, becomes just as ‘hard’ (or as nonnegotiable) as a physical condition.³³

33It is nevertheless thinkable that the social phenomenon of the free market could become a political point of debate, so that, for instance, via subsidies, boundary conditions with respect to cost price could be renegotiated. For physical and technical conditions, such a scenario is unthinkable; we cannot negotiate ourselves in a different kind of physical reality, even though we might want to.

6.5. THE EVOLUTION OF CIVIL AVIATION 99