Increasing Entropy

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When all three lights I see ahead,
I turn to Starboard and show my Red:
Green to Green, Red to Red,
Perfect Safety — Go Ahead.

But if to Starboard Red appear,
It is my duty to keep clear —
To act as judgment says is proper:
To Port or Starboard, Back or Stop her.

And if upon my Port is seen
A Steamer’s Starboard light of Green,
I hold my course and watch to see
That Green to Port keeps Clear of me.

Both in safety and in doubt
Always keep a good look out.
In Danger, with no room to turn,
Ease her, Stop her, Go Astern.