The pleasures of mental agility are much overstated, inevitably - as it now appears to me - by those not exclusively dependent upon them.
It would be suicide in the American academy to show too early an interest beyond your doctoral specialization: charges of everything from charlatanry to ambition would be levied and tenure denied. I've seen this first-hand.
There is nothing to be said for being crippled. You don't see the world better or clearer, nor do you develop some special set of skills by way of compensation.
What has gone catastrophically wrong in England and the States is that for 30 years we've lost the ability to talk about the state in positive terms. We've raised a generation or two of young people who don't think to ask, 'What can the state do that is good?'