The belief in a cycle of multiple births and deaths, referred to as
samsara, is intrinsically related to the doctrine of karma. The latter
affirms that every volitional action produces a result that is determined
by the nature of the action and the motive that underlies it. Since births
have been multiple, it is readily conceivable that a storehouse of the
effects of previous actions exists that cannot be exhausted in a single
lifetime. Future births are thus necessitated for the purpose of experiencing
the desirable and undesirable consequences of past and present
lives and for the attainment of unfulfilled desires. In these future lives,
the effects of new actions are added to the storehouse of karma and the
cycle of samsara is perpetuated.