"Where we went wrong was getting on a boat," Guildenstern reflects aloud to the ocean breeze. "We can move, of course, change direction, rattle about, but our movement is contained within a larger one that carries us along as inexorably as the wind and current ..."

This part makes sense.   But what is lost to him is how trivial it had seemed when it happened.  At some point, they must have nonchalantly agreed to pay the fee, step on board, as if they do it every day – surely it felt perfectly natural at the time.  And that had been it.  There were no warning signs, no apparent symbolism, no enigmatic predictions or premonitions.  Just a packing of luggage and the carriage ride to the harbor.

... At least, he thinks so -- somehow it’s impossible for him to recall their first actual steps onto the vessel.  He can’t even grasp the very first hollow thump of footsteps on wooden planking.  Only the stray cry of a seagull in pitch darkness, followed by the silhouette of his companion’s face in the lamplight and the shatteringly profound declaration that indeed they, Rosencrantz and Guildenstern, were, in fact, on a boat.

He sighs and curses the open void in his memory.  One would expect that such a pivotal moment would plant itself firmly in one's brain.

He almost feels cheated.

They had locked their fates in a metal box and swallowed the key, he muses, and so carelessly.  If only they had looked before they leapt.

Looked for what?  He doesn’t know.

Guildenstern vaguely recalls an earlier thought that he would like to spend most of his life on boats.  A bitter laugh catches hard in his throat as it occurs to him that he has been on a boat his whole life, just like every creature in existence.

How his mind has changed.  He has realized that the inability to choose the direction of one’s movement is not a blessing but a curse.  

Choosing … ‘choice’ – the word lingers in his mind.  As many crossroads as they had come to, as many options as they were presented with, he wonders how they had managed to make the wrong decision every time.  They had been Rosencrantz and Guildenstern, summoned at dawn to meet Lord Hamlet and henceforth to glean what was afflicting him, drawing him into pleasures and subsequently escorting him to England.  Nowhere in this description of their idle existences was the phrase ‘to deliver a letter to the King ordering their own execution’.  And yet it ambushed them at the very last moment, where there was no hope of turning in any other direction.  Their coup de grâce.

Left to the mercy of the sea, every man has but two choices:  agree to follow the winds and the current, or send himself overboard.

On a boat, one is trapped.  Guildenstern regrets that they hadn’t realized it sooner.