the individuals of the same species, and which come under the present
head of antithesis, it is extremely doubtful, whether any of them
were at first deliberately invented and consciously performed.
With mankind the best instance of a gesture standing in direct opposition
to other movements, naturally assumed under an opposite frame of mind,
is that of shrugging the shoulders. This expresses impotence or
an apology,--something which cannot be done, or cannot be avoided.
The gesture is sometimes used consciously and voluntarily, but it
is extremely improbable that it was at first deliberately invented,
and afterwards fixed by habit; for not only do young children
sometimes shrug their shoulders under the above states of mind,
but the movement is accompanied, as will be shown in a future chapter,
by various subordinate movements, which not one man in a thousand
is aware of, unless he has specially attended to the subject.

Dogs when approaching a strange dog, may find it useful to show by their
movements that they are friendly, and do not wish to fight. When two young
dogs in play are growling and biting each other's faces and legs, it is
obvious that they mutually understand each other's gestures and manners.
There seems, indeed, some degree of instinctive knowledge in puppies
and kittens, that they must not use their sharp little teeth or claws
too freely in their play, though this sometimes happens and a squeal
is the result; otherwise they would often injure each other's eyes.
When my terrier bites my hand in play, often snarling at the same time,
if he bites too hard and I say GENTLY, GENTLY, he goes on biting,
but answers me by a few wags of the tail, which seems to say "Never mind,
it is all fun." Although dogs do thus express, and may wish to express,
to other dogs and to man, that they are in a friendly state of mind,
it is incredible that they could ever have deliberately thought of drawing
back and depressing their ears, instead of holding them erect,--of lowering