Earlier in the story, the alchemist told Santiago when you possess great treasures within you, and try to tell others of them, seldom are you...

At
one point on Santiago's quest for his Personal Legend, he and the alchemist are travelling
together toward the Pyramids. They encounter some armed Arabs that stop the alchemist and
Santiago. The robbers demand to know what Santiago and the alchemist are doing and where they
are going. The alchemist has items that the other men simply do not understand, and the
alchemist's answer mystifies the men.

"What are these
things?" he asked.

"That's the Philosopher's Stone and the Elixir
of Life. It's the Master Work of the alchemists. Whoever swallows that elixir will never be sick
again, and a fragment from that stone turns any metal into gold."

The Arabs' response is to laugh at the answer, and the men then
leave. Santiago immediately asks why the alchemist did that, and the alchemist responds with the
quote in question.

"Are you crazy?" the boy
asked the alchemist, when they had moved on. "What did you do that for?"

"To show you one of life's simple lessons," the alchemist answered.
"When you...