Si cada uno de los instantes de nuestra vida se va a repetir infinitas veces, estamos clavados a la eternidad como Jesucristo a la cruz. La imagen es terrible. En el mundo del eterno retorno descansa sobre cada gesto el peso de una insoportable responsabilidad. Ese es el motivo por el cual Nietzsche llamó a la idea del eterno retorno la carga más pesada. Pero si el eterno retorno es la carga más pesada, entonces nuestras vidas pueden aparecer, sobre ese telón de fondo, en toda su maravillosa levedad.
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La carga más pesada nos destroza, somos derribados por ella, nos aplasta contra la tierra. Pero en la poesía amatoria de todas las épocas la mujer desea cargar con el peso del cuerpo del hombre. La carga más pesada es por lo tanto, a la vez, la imagen de la más intensa plenitud de la vida. Cuanto más pesada sea la carga, más a ras de tierra estará nuestra vida, más real y verdadera será. Por el contrario, la ausencia absoluta de carga hace que el hombre se vuelva más ligero que el aire, vuele hacia lo alto, se distancie de la tierra, de su ser terreno, que sea real sólo a medias y sus movimientos sean tan libres como insignificantes.

...burdened with the unbearable weight of ourselves.

I have been made to learn that the doom and burden of our life is bound forever on man’s shoulders; and when the attempt is made to cast it off, it but returns upon us with more unfamiliar and more awful pressure.

In the world of eternal return the weight of unbearable responsibility lies heavy on every move we make. That is why Nietzsche called the idea of eternal return the heaviest of burdens.
If eternal return is the heaviest of burdens, then our lives can stand out against it in all their splendid lightness.
But is heaviness truly deplorable and lightness splendid?
The heaviest of burdens crushes us, we sink beneath it, it pins us to the ground. But in the love poetry of every age, the woman longs to be weighed down by the man's body. The heaviest of burdens is therefore simultaneously an image of life's most intense fulfillment. The heavier the burden, the more real and truthful they become.
Conversely, the absolute absence of a burden causes man to be lighter than air, to soar into the heights, take leave of the earth and his earthly being, and become only half real, his movements as free as they are insignificant.
What then shall we choose? Weight or lightness?
...That is the question. The only certainty is: the lightness/weight opposition is the most mysterious, most ambiguous of all.

The doom and burthen of our life is bound forever on man's shoulders, and when the attempt is made to cast it off, it but returns upon us with more unfamiliar and more awful pressure.

Time is heavy sometimes; imagine how heavy eternity must be.

The heaviest burden: “What, if some day or night, a demon were to steal after you into your loneliest loneliness and say to you: ‘This life, as you now live it and have lived it, you will have to live once more and innumerable times more; and there will be nothing new in it, but every pain and every joy and every thought and sigh and everything unutterably small or great in your life must return to you, all in the same succession and sequence — even this spider and this moonlight between the trees and even this moment and I myself. The eternal hourglass of existence is turned over again and again—and you with it, speck of dust!’ Would you not throw yourself down and gnash your teeth and curse the demon who spoke thus? Or have you once experienced a tremendous moment when you would have answered him: ‘You are a god, and never have I heard anything more divine!’ If this thought were to gain possession of you, it would change you as you are, or perhaps crush you. The question in each and every thing, “do you want this once more and innumerable times more?” would lie upon your actions as the greatest weight. Or how well disposed would you have to become to yourself and to life to crave nothing more fervently than this ultimate eternal confirmation and seal?.

The heaviest burden: “What, if some day or night, a demon were to steal after you into your loneliest loneliness and say to you: ‘This life, as you now live it and have lived it, you will have to live once more and innumerable times more; and there will be nothing new in it, but every pain and every joy and every thought and sigh… must return to you — all in the same succession and sequence — even this spider and this moonlight between the trees and even this moment and I myself. The eternal hourglass of existence is turned over again and again — and you with it, speck of dust!’ Would you not throw yourself down and gnash your teeth and curse the demon who spoke thus? Or have you once experienced a tremendous moment when you would have answered him: ‘You are a god, and never have I heard anything more divine!’ If this thought were to gain possession of you, it would change you as you are, or perhaps crush you. The question in each and every thing, “do you want this once more and innumerable times more?” would lie upon your actions as the greatest weight. Or how well disposed would you have to become to yourself and to life to crave nothing more fervently than this ultimate eternal confirmation and seal?

What a heavy burden is a name that has become too famous.

To be the best in the world in anything, even 'long distance spitting', implies a grave, heavy and suffocating responsibility.

The necessity of knowing a little about a great many things is the most grievous burden of our day. It deprives us of leisure on the one hand, and of scholarship on the other.

Light burdens, long borne, grow heavy.

With great power, comes great responsibility.

man being condemned to be free carries the weight of the whole world on his shoulders; he is responsible for the world and for himself as a way of being.