Philosopher Søren Kierkegaard said that life can only be understood backward but it must be lived forward.

Life can only be understood backward; the trouble is, it has to be lived forward.

Life can only be understood going backward, but must be lived going forward.

It is quite true what Philosophy says: that Life must be understood backwards. But that makes one forget the other saying: that it must be lived — forwards. The more one ponders this, the more it comes to mean that life in the temporal existence never becomes quite intelligible, precisely because at no moment can I find complete quiet to take the backward- looking position.

History including that of evolution is just "one damned thing after another We can explain in hindsight what has happened but we cannot predict what will happen in the future. The Danish philosopher Søren Kierkegaard expressed the same view in his famous phrase "Life is understood backwards, but must be lived forwards.

It is perfectly true, as the philosophers say, that life must be understood backwards. But they forget the other proposition, that it must be lived forwards.

It is really true what philosophy tells us, that life must be understood backwards. But with this, one forgets the second proposition, that it must be lived forwards. A proposition which, the more it is subjected to careful thought, the more it ends up concluding precisely that life at any given moment cannot really ever be fully understood; exactly because there is no single moment where time stops completely in order for me to take position [to do this]: going backwards.

la vida sólo puede ser entendida mirando hacia atrás; aunque deba ser vivida mirando hacia adelante

Life is lived forward but is judged in reverse.

Kierkegaard was by far the most profound thinker of the last century. Kierkegaard was a saint.

Now ordinary people are born forwards in Time, if you understand what I mean, and nearly everything in the world goes forward too. This makes it quite easy for the ordinary people to live, just as it would be easy to join those five dots into a W if you were allowed to look at them forwards, instead of backwards and inside out. But I unfortunately was born at the wrong end of Time, and I have to live backwards from in front, while surrounded by a lot of people living forwards from behind. Some people call it having second sight.
~Merlin

To look forward, to want life, means we have to be willing to look backwards and become more conscious of all those who have hurt us, all that is broken in us and that has brought us inner deaths, hurts that we may have hidden and stifled. It means that we acknowledge the story of our origins, of our own lives, see and accept our brokenness and the times we also have hurt others. When we have accepted who we are and what we need in order to grow in compassion and peacemaking, we can move forward to give life. To forgive is a gift of God that permits us to let go of our past hurts.

Our lives can only be interpreted in retrospect, yet must be lived from day to day, blindly. What folly, the human condition!

Kierkegaard is a new world of thought, a rare mental atmosphere in which we live dangerously, as many people have already discovered at the cost of their complacency. .... To begin reading Kierkegaard is to embark on a long journey, a journey which will be difficult and dangerous, but with such a reward at the end that all the incidental pain will be immediately forgotten. Kierkegaard’s life was in every sense that of a saint. He is perhaps the most real saint of modern times. p. 251-252, 255