What is the symbolic meaning of "All the world's a stage" by Shakespeare in As You Like It?

The soliloquy of Jacques in As You Like
It is not symbolic but metaphorical. The extended metaphor has two main
parts. In the first part he is saying that everybody in the world is an actor on a
gigantic stage all at the same time. It is one vast stage production. Then in the second
part Jacques focuses on one individual actor and declares that he has to play seven
parts during his lifetime. He describes each of the roles every man must play, if he
lives long enough, beginning as an infant, gradually becoming a boy, and so on
inexorably until he reaches the last stage of all as a very old man ready to
die.

What is intriguing about this soliloquy is that we
recognize the truth in it. We remember various "roles" we played in our past and how we
somehow seemed to be assigned new roles and learned to play them after feeling a little
awkward in them at first. We recognize how we are often "playing a part" when we are at
work or at a social gathering, and we realize that other people must be doing the same
thing.

These "roles" or "parts" are now called "personas"
by psychologists, and the term has become part of the common language. When are we
really ourselves? Probably only when we are alone--if then. The rest of the time, to use
T. S. Eliot's words, we "put on a face to meet the faces that we meet." Shakespeare,
through his character Jacques, is telling an important truth about mankind and human
society. What does "All the world's a stage" mean? It means that all the world's a
stage.