therefore, ascribe a result which is so invariably precise to such an
obscure condition of mind as is implied when the word presentiment is
used; on the contrary, this absolute certainty is so characteristic a
feature of instinctive actions, that it constitutes almost the only
well-marked point of distinction between these and actions that are
done upon reflection. But from this it must again follow that some
principle lies at the root of instinct other than that which
underlies reflective action, and this can only be looked for in a
determination of the will through a process that lies in the
unconscious, {115a} to which this character of unhesitating
infallibility will attach itself in all our future investigations.

Many will be surprised at my ascribing to instinct an unconscious
knowledge, arising out of no sensual impression, and yet invariably
accurate. This, however, is not a consequence of my theory
concerning instinct; it is the foundation on which that theory is
based, and is forced upon us by facts. I must therefore adduce
examples. And to give a name to the unconscious knowledge, which is
not acquired through impression made upon the senses, but which will
be found to be in our possession, though attained without the
instrumentality of means, {115b} I prefer the word "clairvoyance"
{115c} to "presentiment," which, for reasons already given, will not
serve me. This word, therefore, will be here employed throughout, as
above defined.

Let us now consider examples of the instincts of self-preservation,
subsistence, migration, and the continuation of the species. Most
animals know their natural enemies prior to experience of any hostile
designs upon themselves. A flight of young pigeons, even though they
have no old birds with them, will become shy, and will separate from