The Great Filter

We often hear people say that we have to pass through the Great Filter. What does that actually mean? This is something we can talk about today.

As mankind and technology evolves in the future, it is the nature of life that we will eventually become multi planet species. Colonizing stars nearby and eventually galaxies nearby. This seem to be a principle that is true across civilization. And with 500 billion planets in the Milky Way and 10 billion Earth link planets, we have been observing zero signs of higher intelligence. This leads us to the main question, are we the only one and why? To answer this question, the theory of the Great Filter then kicks in. Is it because coming to where we are at right now is something almost impossible and so difficult that we are only civilization that made it to this stage so far? Or is there something even more difficult ahead of us that it is filtering every other civilizations to get through in achieving the goal of becoming a multi planet / stars civilization. And that something difficult is the concept of the Great Filter.