The mistakes and unresolved difficulties of the past in mathematics have always been the opportunities of its future.
Science makes no pretension to eternal truth or absolute truth. 
The longer mathematics lives the more abstract - and therefore, possibly also the more practical - it becomes.
It is the perennial youthfulness of mathematics itself which marks it off with a disconcerting immortality from the other sciences. 
Euclid taught me that without assumptions there is no proof. Therefore, in any argument, examine the assumptions.
Fashion as King is sometimes a very stupid ruler.
