Samsara is the idea of past lives, of reincarnation. This idea comes from the earliest spiritual traditions: Buddhism, Taoism, Jainism, and Hinduism all share in the belief of past lives that are influenced by Karma, or actions one takes during the course of a lifetime. Even the ancient Greek philosopher Plato, one of the first creators of the idea of celestial archetypes or form, believed in the infinite quality of the soul which can achieve liberation through unity with the divine.
These traditions are most likely influenced by the Upanishads, which were written around 600 BC. The ideas of Moksha, liberation/salvation of the soul; Brahman, the nature of the ultimate reality; and Sruti, truths were all passed down in oral tradition from teacher to student. Upanishad is Sanskrit for “sitting down near” which refers to the spread of the ancient knowledge and they were initially kept secret, though they had multiple authors.
I don’t think that the passing of energy is as simple as past lives. One needs to take into consideration the constant flow of conscious energy, rather than accumulation and release into a new life-form upon death. The laws of thermodynamics teaches us that energy is neither created or destroyed, it is simply transformed. Therefore the conscious energy that we receive, consume, and generate is neither created nor destroyed, only transferred between beings and forms. I think that this theory is far more likely than some idealistic view of heaven, rooted an old Norse idea exemplified in Beowulf. Many languages use the same word for sky and heaven.
I believe that a transfer of conscious energy is the key to understanding what the concept of Samsara truly means. Each day, the people we interact with, talk with, share space and time with are the people we spread our consciousness to. This is why we truly live on through our children and the people we influence on a daily basis, while we transfer our consciousness on a daily basis. Maybe we do, in fact, rebirth our energies over time and space in a fashion similar to the belief of Buddhists. Consider that each star has a gravitational effect on each person on the Earth, though slight. Maybe the system we are considering is too large for our minds to truly comprehend.
Basically, I am saying that we should not just jump to conclusions about having a past life, because we really don’t know. I have heard about children claiming to have been master painters in past lives, but honestly, if they can’t reproduce the work the point is moot. That would lead me to believe the “gifted” child’s beliefs are a result of parental influence rather than subjective conscious experience. But the key is the concept, that conscious energy spreads through each of our actions and thoughts and that our actions truly do echo throughout eternity.