Life, as we know it, is incredibly fragile. It requires a very precise balance of various forces. Heat vs. cold, pressure, gravity, radiation… a slight disturbance results in discomfort, a just a little larger change in one of the variables means death.
Moreover, every now and then there is a crisis that may end in the destruction of life.
The first crisis happened right after chaos fell back enough for life to evolve, when there were merely proto-bacteria in existence. (I ask all educated readers to forgive my oversimplifications). These simply absorbed dead matter, and grew. If this process continued like that, soon there would be no food left, and life would have destroyed itself with its own success.
Fortunately, life learned to produce its own food by photosynthesis. After that, the Earth was filled by plant-like-bacteria. And here another critical point was soon reached. If they had managed to exhaust all carbon dioxide, life would have ended.
Life narrowly managed to respond with evolving animal-bacteria that ate the plants and produced carbon dioxide. Whether it was an accident, divine intervention, or the Force, we won’t know.
Here, life again almost destroyed itself with that success. Another crisis appeared because the first animals were designed to live forever, dividing their cells into infinity. This would quickly deplete Earth’s resources, and end in life’s self-destruction.
At that time, life invented death of old age, which helped in establishing the cycle of life and death as we know it today.
Thanks to that, evolution soon began at full speed. Since the new forms of life lived short lives, they had to learn to adapt to their environments; they had to be able to learn quickly. The previous forms were basically passive vegetable-like jelly in the ocean, the new ones were fighters and learners. This resulted in complexification of the nervous system, and lead to life as we know it today.
Today we face another crisis, one of the kind that could wipe life of the face of the Earth and of the Universe. It’s nature is very complicated (atomic weapons, environmental pollution etc.), but basically the essence of the crisis is that humans have gained enough power to destroy themselves, and at the same time are not fully in control of it – for example, some nuclear weaponry is in the hands of terrorists and despotic states etc.
The point is that there are moments when the balance of light vs. dark collapses, and you cannot count on it to keep life in existence. Then, you have to intervene actively. Remember, we have free will, and it is we conscious beings who dictate the course of events, who choose light over darkness or the other way around. That is the role of the Jedi – to give an example of responsibility, to see the greater picture, too look at things globally.
Of course, all it not lost yet. Life, as usual, is defending itself pretty well: the Club of Rome (personally, I believe all Jedi should know and support the Club of Rome), all the scientists working on solving our crisis, various organisations, the Jedi, all the good people around the world – yes, clearly there is reason for hope.
But, as always, the life threshold is incredibly narrow. We, the humanity, must not make one mistake too many … Be mindful.