according to the theory of "eternal return", where one is fixed to repeat their own life over and over again infinitely, the people who populate your lives each
time are split into
two categories:
constants are those that
will ALWAYS be there with each cycle (family, parents, siblings, children, the individuals you had those children with)
variables are those that change with each cycle, that are not always present around you each
time (friends, co-workers)