第9章 「外界」 n.7 - 事象を一つの束に集める方法
ひとつの与えられた対象(物)の、異なる場所から見られる種々の現われ(appeasrance)は、それらが「規則的(regular)」であるかぎり、視覚的である場合は遠近法(laws of perspective)によって結びついており、眼以外の感覚によって認められる場合は、いくらか遠近法と似かよった法則によってむすびついている。(注:たとえば、音の場合は近くにある場合は大きく、遠くにある場合は小さく、聞こえるといったところか?) |
Chapter 9 The External World, n.7There are, in this theory, two ways of collecting events into bundles. On the one hand, you may make a bundle of all the events which can be considered as appearances of one 'thing'. Suppose, for example, that the thing concerned is the sun. You have, to begin with, all the visual percepts of the people who are seeing the sun. Next, you have all the photographs of the sun that are being taken by astronomers. And lastly, you have all those occurrences at various places in virtue of which it would be possible to see or photograph the sun at those places. The whole of this bundle of events is causally connected with the sun of physics. The events proceed outward with the velocity of light from the place in physical space where the sun is. As they proceed outward from the sun, their character changes in two ways. There is first what may be called a 'regular' way, which consists of a diminution of size and intensity in accordance with the inverse square law. To a fairly close degree of approximation, this kind of change is alone operative in empty space. But the aspects presented by the sun in places where there is matter change in ways which depend upon the nature of the matter. Mist will make the sun look red, thin clouds will make it look dim, completely opaque matter will make it cease to present any appearance at all. (When I speak of 'appearance', I am not thinking only of what people see, but also of occurrences connected with the sun in places where there is no percipient.) When the intervening medium contains an eye and an optic nerve, the resulting appearance of the sun is what somebody actually sees.The appearances of a given object from different places, so long as they are 'regular', are connected by the laws of perspective when they are visual and by not wholly dissimilar laws when they are such as would be revealed by other senses. |