From the Preface:
All dreams possess an element of warning or prescience;
some more than others. This is unknown to the many, but is known
to the observing few. There are many people who have no natural
taste for music, and who do not know one note from another.
There are also those who cannot distinguish one color from another.
To the former there is no harmony of sound, and to the latter
there is no blending of colors.

They are heard and seen, but there is no artistic recognition of the same.
Still it would be absurd to say to either the musician or the artist:
your art is false and is only an illusion of the senses.

One man apparently never dreams; another dreams occasionally,
and still another more frequently; none atttempt{sic} to interpret
their dream, or to observe what follows; therefore, the verdict is,
``There is nothing in dreams.'' (Schopenhauer aptly says:
``No man can see over his own height.... Intellect is invisible
to the man who has none.'') The first is like the blind man who
denies the existence of light, because he does not perceive it.
The second and third resemble the color-blind man, who sees
but who persists in calling green blue, and vice versa.

A fourth man sees in a dream a friend walking in his room;
the vision is so vivid he instantly gets up and strikes a match.
After making sure there is no intruder about the room he looks
at his watch and goes back to bed. The next day he receives
the unwelcome tidings that his friend died at the exact moment
of the vision.