I turn aside with a shudder of horror from this lamentable plague of functions which have no derivatives.
Abel has left mathematicians enough to keep them busy for 500 years.
There exists, if I am not mistaken, an entire world which is the totality of mathematical truths, to which we have access only with our mind, just as a world of physical reality exists, the one like the other independent of ourselves, both of divine creation.
We are servants rather than masters in mathematics.
