hut up to ideas? "Thus I see, whilst I write this," says Locke,[1] "I
can change the appearance of the paper, and by designing the letters
tell beforehand what new idea it shall exhibit the very next moment, by
barely drawing my pen over it, which will neither appear (let me fancy
as much as I will), if my hand stands still, or though I move my pen,
if my eyes be shut; nor, when those characters are once made on the
paper, can I choose afterward but see them as they are; that is, have
the ideas of such letters as I have made. Whence it is manifest, that
they are not barely the sport and play of my own imagination, when I
find that the characters that were made at the pleasure of my own
thought do not obey them; nor yet cease to be, whenever I shall fancy
it; but continue to affect the senses constantly and regularly,
according to the figures I made them."

Locke is as bad as Descartes. Evidently he regards himself as able to
turn to the external world and perceive the relation that things hold
to ideas. Such an inconsistency may escape the writer who has been
guilty of it, but it is not likely to escape the notice of all those
who come after him. Some one is sure to draw the consequences of a
doctrine more rigorously, and to come to conclusions, it may be, very
unpalatable to the man who propounded the doctrine in the first
instance.

The type of doctrine represented by Descartes and Locke is that of
_Representative Perception_. It holds that we know real external
things only through their mental representatives. It has also been
called _Hypothetical Realism_, because it accepts the existence of a
real world, but bases our knowledge of it upon an inference from our
sensations or ideas.

49. THE STEP TO IDEALISM.--The admirable clearness with which Locke
writes makes it the easier for his reader to detect the untenability of
his position. He uses simple language, and he never takes refuge in
vague and ambiguous phrases. When he tells us that the mind is wholly
shut up to its ideas, and then later assumes that it is not shut up to
its ideas, but can perceive external things, we see plainly that there
must be a blunder somewhere.

George Berkeley (1684-1753), Bishop of Cloyne, followed out more
rigorously the consequences to be deduced from the assumption that all
our direct knowledge is of ideas; and in a youthful work of the highest
genius entitled "The Principles of Human Knowledge," he maintained that
the