The days of exploration of Shackleton and Scott are long gone. Everything has been climbed, crossed, done. Now what we're exploring are the full boundaries of human endeavour. It's not physical - it's all in the head.
A body seriously out of equilibrium, either with itself or with its environment, perishes outright. Not so a mind. Madness and suffering can set themselves no limit.
We can only feel sorry for ourselves when our misfortunes are still supportable. Once this limit is crossed, the only way to bear the unbearable is to laugh at it.
I continuously go further and further learning about my own limitations, my body limitation, psychological limitations. It's a way of life for me.
Borders I have never seen one. But I have heard they exist in the minds of some people.
Few topographical boundaries can rival the frontiers of the mind.
Ah! The strength of women comes from the fact that psychology cannot explain us. Men can be analyzed, women...merely adored.
Recounting of a life story, a mind thinking aloud leads one inevitably to the consideration of problems which are no longer psychological but spiritual.
Ask the guys who are doing serious triathlons if there are any limits to what can be done. The limit is right here. You've got to get physically fit between the ears. Muscles don't know anything. They have to be taught.
Most SF is about madness, or what is currently ruled to be madness; this is part of its attraction - it's always playing with how much the human mind can encompass.
There's nothing that defines who you are more than boundaries, whether you cross them or not, in every aspect of your life, and horror is a really great boundary.
Experience teaches that for most people there is a limit beyond which their constitution cannot comply with the demands of civilization. All who wish to reach a higher standard than their constitution will allow, fall victims to neurosis. It would have been better for them if they could have remained less "perfect".
And perhaps there is a limit to the grieving that the human heart can do. As when one adds salt to a tumbler of water, there comes a point where simply no more will be absorbed.