The story of a theory's failure often strikes readers as sad and unsatisfying. Since science thrives on self-correction, we who practice this most challenging of human arts do not share such a feeling. We may be unhappy if a favored hypothesis loses or chagrined if theories that we proposed prove inadequate. But refutation almost always contains positive lessons that overwhelm disappointment, even when […] no new and comprehensive theory has yet filled the void.

After the first proof [of 'Sphere Spirals'] my high expectations were, as always, greatly disappointed. I am now struggling on - with some feeling of despair - so that I at least achieve a passable result.

Your discovery of the contradiction caused me the greatest surprise and, I would almost say, consternation, since it has shaken the basis on which I intended to build arithmetic.

There is much to be said for being a mathematician. To begin with, he has to be completely honest in his work, not from any superior morality, but because he simply cannot get away with a fake. ... A mathematician's normal day contains hours of close concentration, and leaves him jaded in the evening. ... This is why we tend to relax either on mild nonfiction like biographies, or - to be crude, and to the derision of arts people - on trash. There is, of course, good trash and bad trash. ... Minor depressions will occur, and most of a mathematician's life is spent in frustration, punctuated with rare inspirations. A beginner can't expect quick results; if they are quick they are pretty sure to be poor. ... When one has finished a substantial paper there is commonly a mood in which it seems that there is really nothing in it. Do not worry, later on you will be thinking 'At least I could do something good then.' At the end of a particularly long and exacting work there can be a strange melancholy. This, however, is romantic, and mildly pleasant, like some other melancholies.

My faculty for disappointment surpasses understanding. It is what lets me comprehend Buddha, but also what keeps me from following him.

The limits of science have always been the source of bitter disappointment when people expected something from science that it was not able to provide. Take the following examples: a man without faith seeking to find in science a substitute for his faith on which to build his life; a man unsatisfied by philosophy seeking an all-embracing universal truth in science; a spiritually shallow person growing aware of his own futility in the course of engaging in the endless reflections imposed by science. In every one of these cases, science begins as an object of blind idolatry and ends up as an object of hatred and
contempt. Disenchantment inevitably follows upon these and similar misconceptions. One question remains: What value can science possibly have when its limitations have become so painfully clear?

Disappointment is a sort of bankruptcy - the bankruptcy of a soul that expends too much in hope and expectation.

Disappointment is educational

The great question in disappointment is whether we allow it to bring us to ground, to a firmer sense of our self, a surer sense of the world, and what is good and possible for us in that world, or whether we experience it only as a wound that make us retreat from further participation.

I believe that this danger of the mathematician making mistakes is an unavoidable corollary of his power of sometimes hitting upon an entirely new method. This seems to be confirmed by the well known fact that the most reliable people will not usually hit upon really new methods.

There is no need for disappointment at the failure of the model to give perfect agreement with observation; it has served its purpose, for it has distinguished what are the features of the actual which require new conditions for their explanation.

To be disappointed is to reassess our self and our inner world, and to be called to the larger foundational reality that lies beyond any false self we had only projected upon the outer world.

The frustration was with the philosophy of the instrument.

I told graduates to not be afraid to fail, and I still believe that. But today I tell you that whether you fear it or not, disappointment will come. The beauty is that through disappointment you can gain clarity, and with clarity comes conviction and true originality.