People
The very substance of the ambitious is merely the shadow of a dream.
— William Shakespeare · Hamlet
Behind the line May contain spoilers.
Our reading
An editorial interpretation.
Ambition, in this view, is made of very thin stuff. What ambitious people chase is only the shadow of a dream, so it's a reflection of something already insubstantial. The image suggests striving can feel weighty while being mostly airy and unreal.
Context reviewed