What are the visual laws which will help the architect in the design process? Some of the laws are of a physiological nature, such as ocular stereometry, sensitivity of the retina, adaptation of the iris to the level of lighting, angle and precision of view, etc. They are important, but we will not tackle them here, because numerous works on physiology and architecture, lighting engineering or technical design are already easily accessible.
Other laws originated from the psychology of perception and more especially from ‘Gestalt’ theories (the theory of form). They are of interest to us because they frequently impinge on the notion of preferences, which can provide useful elements for an aesthetic theory. The first part of this book refers to this. It will be easily recognizable in the chapters ‘Order and Disorder’, ‘Fabric and Object’ and ‘Space’.
The third group of theories concentrates on the mental activity which draws on perception. We are thinking of epistemology, information theory, genetics, anthropology, etc., which will appear in a more generalized manner, particularly in the chapter on ‘place’. What interests us for the moment is that some principles of the psychology of perception can be applied to architecture and to the graphic arts, since they originated from empirical experiments on vision, instead of being speculative.
鲁道夫·阿恩海姆和恩斯特·格姆布里希将格式塔心理学扩展到了艺术领域。布鲁诺·泽维(Bruno Zevi)在他的《教与学如何看待建筑》(‘classic’ on teaching, Learning how to see architecture)一书中，以一种相关的、说教的方式运用了其中的一些原则。二十多年前，克里斯蒂安·诺伯格-舒尔茨(Christian Norberg-Schulz)首次尝试提出一种建筑形式理论，该理论至少部分地基于感知原理。
Rudolf Arnheim and Ernst Gombrich have helped to extend Gestalt psychology to art. Bruno Zevi has used some of its principles in a relevant and didactic way in his ‘classic’ on teaching, Learning how to see architecture. Christian Norberg-Schulz, more than twenty years ago, made a first attempt at proposing a theory of architectural form which would be based, at least partially, on the principles of perception.
Norberg-Schulz subsequently disassociated himself from an explanation of the nature of the architectural phenomenon from the point of view of visual perception. However, it cannot be denied that, without eyes, one’s experience of the physical environment is quite different. Numerous works on the perception of the blind exist as evidence of this.
A figure finds its autonomy to a large extent by its edges, its contours, therefore by the contact it has with its exterior, the rest of the world. It is not accidental if in classical architecture the base, corners and cornice are accentuated. It is as if there were a greater concentration of information and excitation at the edge than at other points. The background can also consist of figures itself, but they play a secondary role.
There are rules which govern the good fit of figures; it is a question of the formal characteristics which tend to make them dominant in relation to other forms in the visual field. When the shape is relatively convex, small and closed (for example the moon, a window, etc. Figure 13 ) and when it contrasts with a ground which, on the other hand, seems to extend indefinitely, it tends to become a figure. The presence of elementary geometric form rein- forces this tendency towards an autonomous figure (for example circle, spiral, prism, etc). A weakly defined figure can, however, become a good fit when we are familiar with it.
Autonomy and formal identity must not be confused. Identity can come from its outline, but just as much from associated information that can be discerned on its surface or in its volume (for example the human face with nose, mouth, eyes; the rose with its petals; the cathedral with its doorway, buttresses and turrets). We shall come back later on to this not-so-innocent eye.
It is an area where the complementary nature of the relationship between figure and ground can be used as a graphic tool by architects in order to get a clearer idea of the form of spaces. When we draw a plan, we give concrete expression to the walls and objects; we draw what surrounds the space rather than the space itself . If we wanted to perceive better the form of the spaces themselves, we would have to transform the volume into a figure. That can be done by drawing the surfaces rather than the walls which define them. It would then be a question of a sort of working with the negative. But it is not sufficient simply to present a negative plan, because one would again read the white lines which were black before. That is due to the law which requires a ground to have an ‘infinite’ field relative to the figure . This same technique can be applied with more subtlety by using shades of black and grey according to the degree of enclosures of a space (explicit or implicit), or by reflecting the relief of the ceiling for example.
Arnheim suggests that architects should replace the notion of figure/ ground by that of objects producing a field of energies. The space would then be described by vectors or ‘magnetic fields’ modified by distances, expansions and contractions. He thus is interested in the work of Paolo Portoghesi whose ‘grids’ bear a greater resemblance to ripples produced by the walls than to a system of abstract organization. The notion of figure and its relationship with ground will be very useful elsewhere when we talk about fabric and object.
Although these laws often act very forcefully on our images, we must not lose sight of the fact that our perceptions are not only the result of a ‘mechanical process’ of vision, but that they are filtered through our memory and intelligence.