t you abused the police," replied the
other. "I found that there was a special opening in the service
for those whose fears for humanity were concerned rather with the
aberrations of the scientific intellect than with the normal and
excusable, though excessive, outbreaks of the human will. I trust I make
myself clear."

"If you mean that you make your opinion clear," said Syme, "I suppose
you do. But as for making yourself clear, it is the last thing you do.
How comes a man like you to be talking philosophy in a blue helmet on
the Thames embankment?"

"You have evidently not heard of the latest development in our police
system," replied the other. "I am not surprised at it. We are keeping it
rather dark from the educated class, because that class contains most
of our enemies. But you seem to be exactly in the right frame of mind. I
think you might almost join us."

"Join you in what?" asked Syme.

"I will tell you," said the policeman slowly. "This is the situation:
The head of one of our departments, one of the most celebrated
detectives in Europe, has long been of opinion that a purely
intellectual conspiracy would soon threaten the very existence of
civilisation. He is certain that the scientific and artistic worlds are
silently bound in a crusade against the Family and the State. He has,
therefore, formed a special corps of policemen, policemen who are also
philosophers. It is their business to watch the beginnings of this
conspiracy, not merely in a criminal but in a controversial sense. I am
a democrat myself, and I am fully aware of the value of the ordinary
man in matters of ordinary valour or virtue. But it would obviously be
undesirable to employ the common policeman in an investigation which is
also a heresy hunt."

Syme's eyes were bright with a sympathetic curiosity.

"What do you do, then?" he said.

"The work of the philosophical policeman," replied the man in blue, "is
at once bolder and more subtle than that of the ordinary detective.
The ordinary detective goes to pot-houses to arrest thieves; we go
to artistic tea-parties to detect pessimists. The ordinary detective
discovers from a ledger or a diary that a crime has been committed. We
discover from a book of sonnets that a crime will be committed. We have
to trace the origin of those dreadful thoughts that drive men on at last
to intellectual fanaticism and intellectual crime. We were only just in
time to prevent the assassination at Hartle