Recursion

Each time a character uses the chair to travel back in time, their body dies in the deprivation tank, and they go to another moment in time. As the characters die and they return to life, these moments constitute a kind of rebirth. The symbol of the tank underlines this motif, as it looks like a large egg. By entering this egg, the characters are symbolically reentering the womb.

Both Barry and Reed experience moments in which they wish to return to infancy. When Reed regains memories of dying in the tank, he says that all the memories of his life played before his eyes, right back to being a baby with his family. He breaks down in tears, remembering what it felt like to be surrounded by love before he got addicted to heroin. Similarly, when Barry maps the memory that will take him back to the original timeline, he witnesses many of his memories in quick succession. The memory of being a baby entices him, as life was safe and uncomplicated, but he forces himself to return to the correct moment.