first place; it is driven away by others, which are displaced in turn by
still others emerging from the penumbra. On the contrary, in attention
(relative monoideism) a single image retains first place for a long time
and tends to have the same importance again. Finally, in a condition of
obsession (absolute monoideism) the fixed idea defies all rivalry and
rules despotically. Many inventors have suffered painfully this tyranny
and have vainly struggled to break it. The fixed idea, once settled,
does not permit anything to dislodge it save for the moment and with
much pain. Even then it is displaced only apparently, for it persists in
the unconscious life where it has thrust its deep roots.

At this stage the unifying principle, although it can act as a stimulus
for creation, is no longer normal. Consequently, a natural question
arises: Wherein is there a difference between the obsession of the
inventor and the obsession of the insane, who most generally destroys in
place of creating?

The nature of fixed ideas has greatly occupied contemporary alienists.
For other reasons and in their own way they, too, have been led to
divide obsession into two classes, the intellectual and emotional,
according as the idea or the affective state predominates. Then they
have been led to ask: Which of these two elements is the primitive one?
For some it is the idea. For others, and it seems that these are the
more numerous, the affective state is in general the primary fact; the
obsession always rests on a basis of morbid emotion and in a retention
of impressions.[34]

But whatever opinion we may hold on this point, the difficulty of
establishing a dividing line between the two forms of obsession above
mentioned remains the same. Are there characters peculiar to each one?

It has been said: "The physiologically fixed idea is normally longed
for, often sought, in all cases accepted, and it does not break the
unity of the self." It does not impose itself fatally on consciousness;
the individual knows the value thereof, knows where it leads him, and
adapts his conduct to its requirements. For example, Christopher
Columbus.

The pathological fixed idea is "parasitic," automatic, discordant,
irresistible. Obsession is only a special case of psychic
disintegration, a kind of doubling of consciousness. The individual
becomes a person "possessed," whose self has been confiscated for the
sake of the fixed idea, and whose submission to his s