It was easy to say, easy to do.

To stop swimming: there was no mystery in that, if he could do it.

Could he?
And he could not.

He knew it instantly.

He was aware instantly of an opposition in his members, unanimous and invincible, clinging to life with a single and fixed resolve, finger by finger, sinew by sinew; something that was at once he and not he--at once within and without him;--the shutting of some miniature valve in his brain, which a single manly thought should suffice to open--and the grasp of an external fate ineluctable as gravity.