al processes, we are forced
to conclude that, at the place where the plate is, and at all places
between it and a star which it photographs, SOMETHING is happening which
is specially connected with that star. In the days when the aether was
less in doubt, we should have said that what was happening was a certain
kind of transverse vibration in the aether. But it is not necessary
or desirable to be so explicit: all that we need say is that SOMETHING
happens which is specially connected with the star in question. It
must be something specially connected with that star, since that star
produces its own special effect upon the plate. Whatever it is must be
the end of a process which starts from the star and radiates outwards,
partly on general grounds of continuity, partly to account for the fact
that light is transmitted with a certain definite velocity. We thus
arrive at the conclusion that, if a certain star is visible at a certain
place, or could be photographed by a sufficiently sensitive plate at
that place, something is happening there which is specially connected
with that star. Therefore in every place at all times a vast multitude
of things must be happening, namely, at least one for every physical
object which can be seen or photographed from that place. We can
classify such happenings on either of two principles:

(1) We can collect together all the happenings in one place, as is done
by photography so far as light is concerned;

(2) We can collect together all the happenings, in different places,
which are connected in the way that common sense regards as being due to
their emanating from one object.

Thus, to return to the stars, we can collect together either--

(1) All the appearances of different stars in a given place, or,

(2) All the appearances of a given star in different places.

But when I speak of "appearances," I do so only for brevity: I do not
mean anything that must "appear" to somebody, but only that happening,
whatever it may be, which is connected, at the place in question, with a
given physical object--according to the old orthodox theory, it would be
a transverse vibration in the aether. Like the different appearances
of the table to a number of simultaneous observers, the different
particulars that belong to one physical object are to be collected
together by continuity and inherent laws of correlation, not by their
supposed causal connection with an unknown assumed existent called a