The concept of “eternal return” is understood as the creation after –and paradoxically despite of- the previous extinction and destruction of what existed before. 
The image of the ouroboros –a snake eating its own tale- exemplifies the perfect cycle and movement of any apparently static existence. 
The “Law of conservation of matter” addresses to the same eternal return that authors like Nietzsche or Kundera have repeatedly talked about. 
“Matter cannot be created or destroyed, it can only be changed from one form to another”. This principle was noticed by Mihail Lomonósov and Antoine Lavoisier in different years, 1748 and 1785 respectively. 

Just as it seems easy and intuitive to understand this concept on a small scale, when the observer takes a few steps back, the Whole rises with millions of details that no one could pay attention to individually if intention was not used. 
The sum of units becomes -automatically- unit. 

When Carlota decided to reinterpret Matisse’s “La danse I”, she was just including herself -and other five women- within the inevitable patterns that rule the eternal return. Concept printed in the back of her right arm with a tiny circle. -I’m feeling thrilled by the fact that, sharing our general thoughts on “La danse”, it is precisely now that she reveals the meaning of her tattoo. 
Five women connected by their hands. ¿Where does the first step with the first foot that rises and uproots the bodies from statism start? Probably in the same place where the first pulse with the first hand starts. 
And, if we looked back in time, Matisse was presumably realizing the exact same thing when he saw William Blake’s “Titania, Oberon and Puck with Fairies Dancing” (1786). Who, at the same time, was representing a scene from Shakespeare’s “Midsummer Night’s Dream” (1585). If we kept following the timeline that links these representations, we would go back to the year in which the first heartbeat dazed the fertile land. Or, at least, we would go back to the day when four women were holding hands with their bodies inside the sea but, at the same time, levitating, feeling and understanding the infinite flow of energy travelling between their palms. It is still the same thing, despite the space and time elapsed between one event and another. Five women dancing in a circle. Five bellies united and detached by their hands. Five manes moving through space and time. Convincing the observer that there’s room for the illusion of separation.

“Past and future are two snakes kissing each other in the mouth, past and future is one snake eating its own tale”