gs in gross:

It may be questioned whether a dog _sees_ a rainbow any more
than he apprehends the political constitution of the country in which
he lives. The same principle applies to the kennel in which he sleeps
and the meat that he eats. When he is sleepy, he goes to the kennel;
when he is hungry, he is excited by the smell and color of meat;
beyond this, in what sense does he see an _object?_ Certainly he does not
see a house--_i.e._, a thing with all the properties and relations of a
permanent residence, _unless_ he is capable of making what is present
a uniform sign of what is absent--unless he is capable of thought.[1]

[Footnote 1: Dewey: _How We Think_, p. 17.]

Human beings can respond to objects as _signs_ of other
things, and, what is perhaps more important, can abstract
from those gross total objects certain qualities, features, elements,
which are universally associated with certain consequences.
They can respond to the meaning or bearing of an
object; they can respond to ideas.

To respond to ideas means to respond to significant similarities
in objects and also to significant differences. It
means to note certain qualities that objects have in common,
and to classify these common qualities and their consequences
in the behavior of objects. To note similarities and differences
in the behavior of objects is to enable individuals to act
in the light of the future. The printing on this page would be
to a dog or to a baby merely a blur. To the reader the black
imprints are signs or symbols. To the animal a red lantern is
a haze of light; to a locomotive engineer it is a sign to halt.
To respond to ideas is thus to act in the light of a future. It
makes possible acting in the light of the consequences that
can be foreseen. Present objects or features of objects are
responded to as signs of future or absent opportunities or
dangers. Every time we read a letter, or act in response to
something somebody has told us, we are responding not to
physical stimuli as such, but to those stimuli as signs of other
things.

HUMAN BEINGS ALONE POSSESS LANGUAGE. The value of the
period of infancy in the acquisition of habits and the unique
ability of human beings to respond to ideas is inseparably
connected with the fact that man alone possesses a language,
both oral and written. That is to say, men alone have an
instrument whereby to communicate to each other feelings,
attitudes, ideas, information. To a very limit