The potential elite runner must realize that hard means hard, easy means easy and they must patiently seek out what combinations work for them. They have to learn to be persistent and patient with their training and racing.

A good athlete always mentally replays a competition over and over, even in victory, to see what might be done to improve the performance the next time.

For the novice runner, I'd say to give yourself at least 2 months of consistently running several times a week at a conversational pace before deciding whether you want to stick with it. Consistency is the most important aspect of training at this point.

Why couldn't Pheidippides have died at 20 miles?

You can actually suffer a little bit more going slowly than when you're going really fast. A faster marathon might even be easier than a slow one, in terms of what it takes out of you mentally.

I plan to be running as long as I can and have no plans to stop.

You don't run 26 miles at five minutes a mile on good looks and a secret recipe.