finite. Also the
modification of events by ingression is susceptible of quantitative
differences. Finally therefore we are driven to admit that each object
is in some sense ingredient throughout nature; though its ingression may
be quantitatively irrelevant in the expression of our individual
experiences.

This admission is not new either in philosophy or science. It is
obviously a necessary axiom for those philosophers who insist that
reality is a system. In these lectures we are keeping off the profound
and vexed question as to what we mean by 'reality.' I am maintaining the
humbler thesis that nature is a system. But I suppose that in this case
the less follows from the greater, and that I may claim the support of
these philosophers. The same doctrine is essentially interwoven in all
modern physical speculation. As long ago as 1847 Faraday in a paper in
the _Philosophical Magazine_ remarked that his theory of tubes of force
implies that in a sense an electric charge is everywhere. The
modification of the electromagnetic field at every point of space at
each instant owing to the past history of each electron is another way
of stating the same fact. We can however illustrate the doctrine by the
more familiar facts of life without recourse to the abstruse
speculations of theoretical physics.

The waves as they roll on to the Cornish coast tell of a gale in
mid-Atlantic; and our dinner witnesses to the ingression of the cook
into the dining room. It is evident that the ingression of objects into
events includes the theory of causation. I prefer to neglect this aspect
of ingression, because causation raises the memory of discussions based
upon theories of nature which are alien to my own. Also I think that
some new light may be thrown on the subject by viewing it in this fresh
aspect.

The examples which I have given of the ingression of objects into events
remind us that ingression takes a peculiar form in the case of some
events; in a sense, it is a more concentrated form. For example, the
electron has a certain position in space and a certain shape. Perhaps it
is an extremely small sphere in a certain test-tube. The storm is a
gale situated in mid-Atlantic with a certain latitude and longitude, and
the cook is in the kitchen. I will call this special form of ingression
the 'relation of situation'; also, by a double use of the word
'situation,' I will call the event in which an object is situated 'the
situation of t