An embryonic stem cell is also known as an “uncommitted” cell. It hasn't done anything yet. It doesn't know yet what it wants to do when it grows up… Will it be a brain cell? A liver cell? A bone cell? It has nearly unlimited potential to become nearly anything. However, at some point the cell will differentiate. Following certain environmental or chemical cues, some genes are turned on and others turned off, until the cell develops along a certain pathway. Once it commits, and becomes, say, part of the heart muscle, it cannot switch back. This is how it will remain for the life of the cell.

However, recently it has been discovered that this process is reversible. A group of Japanese researchers, led by Shiniya Yamanaka, won a Nobel Prize in 2012 for the discovery that fully differentiated cells could be induced to return to an embryonic state of unlimited potential.

Through activating just four genes, known as transcription factors, the cell can be reset. All its past “accomplishments” and “life experience” is erased, and it starts again from fresh. It goes back to its primordial state when it can become anything at all. While practical and medical applications are still far off, it is hoped that a patient's own induced cells can be used to treat and cure a number of degenerative diseases.

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Since the dawn of human consciousness, people have had a persistent belief in the immortality of the soul. We may not understand exactly what the soul is or how it gives life to the body, but deep down there is a sense that we will somehow survive our bodily death. In the teachings of Kabbalah we find the concept of reincarnation - after completing its lifespan in one form, the soul often returns to earth in another body, with no memory of its previous existence. This process may repeat itself over and over, with a complete wiping of the slate in between. We do not know, and may never know, for what mission our soul was sent to this world again. In each reincarnation there is something that the soul needs to repair or perfect. Until the goal is met, the soul will continue to be sent back to earth.

However, in our generation there has been a unique development. In the teachings of Kabbalah it is written that the generation of Moshiach is a reincarnation of the generation that left Egypt. Just as G-d performed wonders then, we will soon experience the same wonders. The Lubavitcher Rebbe, has told us that we are the final generation of exile and the first of Redemption. There will be no more cycles of rebirth and return, just the final destination - to live here, in this physical world, eternally, as souls in bodies. In the era of Moshiach, there will be no more death. Every soul that ever lived will return to receive its ultimate reward.