Your ego, your desires, your aims and ambitions.

Those sit like these topmost stones. Sitting upon deeper systems entrenched within you.

The large bottom stone could represent your biology.

Between the biology and the psychology is a special layer.

Whilst our ego, our desires, our ambitions, differ from person to person.

This special layer is the same in all of us.

Understanding it will help with your ego, your ambitions and any interest in psychology.