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.

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

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

It was Kierkegaard who said that life must be lived forward, but it can only be understood backward.

Life is lived forward but is judged in reverse.

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

While we know that history flows forward, it is difficult to realize that we envision it backward. Why is it so?

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

Often people attempt to live their lives backwards: they try to have more things, or more money, in order to do more of what they want so that they will be happier. The way it actually works is the reverse. You must first be who you really are, then, do what you need to do, in order to have what you want. MARGARET YOUNG

The third helpful notion is that it is not enough to think problems through forward. You must also think in reverse, much like the rustic who wanted to know where he was going to die so that he’d never go there. Indeed, many problems can’t be solved forward. And that is why the great algebraist Carl Jacobi so often said, “Invert, always invert,” and why the Pythagoreans51 thought in reverse to prove that the square root of two was an irrational number.

Imagine taking a test knowing the answer. While we know that history flows forward, it is difficult to realize that we envision it backward. Why is it so? We will discuss the point in Chapter 11 but here is a possible explanation: Our minds are not quite designed to understand how the world works, but, rather, to get out of trouble rapidly and have progeny. If they were made for us to understand things, then we would have a machine in it that would run the past history as in a VCR, with a correct chronology, and it would slow us down so much that we would have trouble operating. Psychologists call this overestimation of what one knew at the time of the event due to subsequent information the hindsight bias, the “I knew it all along” effect.

Life is a succession of lessons which must be lived to be understood.

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

What is our life: (Pause.) it’s looking forward or it’s looking back. And that’s our life. That’s it. Where is the moment?