we know directly there are no clear cut distinctions and so no series.
The assumption which we usually make that the facts must consist of
such things as events and qualities and material objects is not based
upon the evidence of direct knowledge: we make the assumption that the
facts must be of this kind simply because they can be explained in
these terms.

It is true that there is some correspondence between the actual facts
and the common sense world of solid tables and so on, and we usually
jump to the conclusion that this correspondence would not be possible
unless the facts had common qualities. There is no denying that facts
can be classified and it seems only natural to take it for granted
that whatever can be classified must share some quality with whatever
belongs to the same class, that, indeed, it is just on account of all
sharing the same common quality that facts can be classified as being
all of the same kind. Thus common sense takes it for granted that all
facts which can be classified as red, and so explained by all the
general laws which we know about the relation of red things to other
things, must share a common quality of redness. It seems only natural
to make this assumption because we are so used to making it, but if we
stop to examine the facts which we know directly we discover that they
do not bear it out, and we are gradually driven to the conclusion that
it is quite unwarranted. It is only bit by bit, as we gradually
accustom ourselves to doubting what we have been accustomed to take
for granted, that we realize how ill this assumption fits the facts.



CHAPTER II