A limit situation is experienced as inevitable, with a feeling of self-ripping. It is a contradictory situation, because it seems to have no way out, but at the same time it contains the possibility of overcoming it. Thanks to Karl Jaspers we have the concept of situation, which he studied in cases of extreme situations.
“We are always in situations. Situations change, opportunities arise. If they are lost they never return. I myself can work to change the situation. But there are situations which remain essentially the same even if their momentary aspect changes and their shattering force is obscured: I must die, I must suffer, I must struggle, I am subject to chance, I involve myself inexorably in guilt. We call these fundamental situations of our existence limit situations. That is to say, they are situations which we cannot evade or change. Along with wonder and doubt, awareness of these ultimate situations is the most profound source of philosophy”.
For Hanna Arendt, who knew and admired him, Jaspers breaks with all philosophical systems, with cosmovisions and “doctrines of the whole”; instead, he deals with “limit situations” and considers existence as a form of freedom. Thus, the human being can, “playing with metaphysics,” feel the borders of the thinkable and overcome them. Unlike Heidegger, for Jaspers, philosophy would be only the preparation for “action” through communication, based on common reason for all. Jaspers knows that the thought of transcendence is doomed to failure. The philosophy of Jaspers, Arendt emphasizes, lies mainly in the ways of his philosophizing. These paths can be drawn from the “dead end” of a positivist or nihilist fanaticism.”
The “dead end” of positivism is the blindness to everything that transcends the object or the subject, thus excluding what can not be defined as something separate and independent. Like the relationship from which something new emerges, when two become one. What Bateson called “the pattern that connects“.
At the opposite pole is the dead end of nihilism. He is the one that arrived Heidegger at the end of his work Being and Time, which led him to admire Hitler and to collaborate for a year with the Nazis as rector of the university. Being, subject to the determination of time, is reduced to being-for-death, doomed to annihilation, that is, to nothingness.
He considered philosophy as a preparation for action in life with others. The same thing that for Oteiza was artistic research: a preparation to get involved with others.
For Jaspers: “The other is constituted for me as a person through my action of being fully myself, that is, communication occurs in the world of being oneself. This is why communication is the most essential of existential tasks, it is the precious and most fragile of the possible achievements.”
The opposite of the bondary situation
Reading the above, one can think that it is fortunate not to have to go through extreme situations. But the truth is that evolution has always occurred in extreme situations. We descend from ancestors who survived extreme situations. In my particular experience, it is in such situations when you learn to value what really matters to you. What really makes sense in your life.
People who spend their lives clinging to safety are reducing their possibilities; and the framework of their life situation is narrowing. They miss the best of themselves, which is what they could have been. 
As happened to the ascidian, a distant ancestor of ours who lost his brain, when he stopped using it.
Existential Pragnanz 