El ciclo eterno

Uroboros "El ciclo eterno" expresses the unity of all things, material and spiritual, which never disappear but perpetually change form in an eternal cycle of destruction and new creation.

In alchemy, the Ouroboros symbolizes the circular nature of the alchemist's work that unites the opposites:
conscious and unconscious, being also a symbol of purification, which represents the eternal cycles
of life and death.

Uroboros or effort also symbolizes eternal, the eternal struggle or wasted effort, since the
cycle begins again in spite of efforts to prevent it.