having been done by a dog
before, or at any rate, something which is not universally admitted to
be doable by a dog. Apparently this willingness to print stories which
enlarge our notions of animal intelligence is regarded in certain
quarters as a sign that the _Spectator_ will swallow anything, and that
its stories must be apocryphal. I cannot, however, help thinking that
all who care for the advancement of knowledge in regard to animals
should be grateful to the editors of the _Spectator_ for not adopting
the plan of excluding all dog stories that do not correspond with an
abstract ideal of canine intelligence. Had they acted on the principle
of putting every anecdote that seemed _prima facie_ unlikely into the
waste-paper basket, they would certainly have missed a great many
stories of real value. In truth, there is nothing so credulous as
universal incredulity. An attitude of general incredulity means a blind
belief in the existing state of opinion. If we believe that animals have
no reasoning power, and refuse to examine evidence that is brought to
show the contrary, we are adopting, the attitude of those who disbelieve
that the earth goes round the sun because they seem daily to see a proof
of an exactly opposite proposition. If people are to refuse to believe
anything of a dog that does not sound likely on the face of it, we shall
never get at the truth about animal intelligence. What is wanted is the
careful preservation and collection of instances of exceptional
intelligence.

III.

Before I conclude this Introduction, I should like to address a word of
apology to the correspondents of the _Spectator_ whose letters form the
present volume. Though the copyright of the letters belongs to the
editors and proprietors of the _Spectator_ I should have liked to ask
the leave of the various writers before republishing their letters.
Physical difficulties have, however rendered this impossible. In the
case of nearly half the letters the names and addresses have not been
preserved. In many instances, again, only the names remain. Lastly, a
large number of the letters are ten or twelve, or even twenty years old,
and the writers may therefore be dead or out of England. Under these
circumstances I have not made any effort to enter into communication
with the writers before including their letters in this book. That their
permission would have been given, had it been asked, I do not doubt. The
original communication of t