When the fishbowl gets too small, it's time to pack up and leave and jump into the lake or ocean.
Zen, like life, defies exact definition, but its essence is the experience, moment by moment, of our own existence -- a natural, spontaneous encounter, unclouded by the suppositions and expectations that come between us and reality. It is, if you like, a paring down of life until we see it as it really is, free from our illusions; it is merely a divestment of ourselves until we recognize our own true nature.