I just started reading GH Hardy's |A Mathematician's Apology;| a book that will probably scare and depress the crap out of me, because I have a horrible fear of growing old. Anyway, I just finished reading the CP Snow foreword (which takes up a good third of the book), whose following comment struck me right in the phobia: Clearly I don't plan to ever be a mathematician, but since mathematics is one of those few professions that truly stretch an individual's mental abilities (in areas of logic, creativity, problem solving, etc.) to their fullest, I figure a mathematician's abilities as he or she ages are highly indicative of the effects of aging on the brain. So is this true? I've looked around and noticed that most important mathematicians and physicists "boomed" around the age of 23-35. This is regardless of whether they were child prodigies (like Newton or Gauss) and got a "head start" or not; the 20's are the magical number it seems. Surely there must be exceptions to the rule. Are there any examples of mathematicians or physicists who made their major contributions late in their life? What about the brain's ability to acquire new skills as it ages? are there any who began their careers later in life? Do I need therapy? :rofl: ... I am seriously mortified of becoming senile, and I'm only 20. Or maybe it's because I'm 20; I find it horribly depressing to think that this is as good as It gets, and that in 10 years I'll begin a slow and inevitable decay. I mean, if a great thinker like GH Hardy felt his mental faculties were performing at less than optimal levels in his 50's and 60's, what hope is there for me to not be a complete vegetable by the time I'm that age. I'd like to think that it's possible to acquire new skills and keep leading a productive creative life well until the end. O God. I'm 21 thursday.