Modes of Pleasure, II - Thom Gunn

(This is Gunn's second poem here.)  I've known this poem for over thirty years and I shudder every time I read it.  I once had it committed to memory, a sentinel and warning against becoming like the speaker.  It's an easy trap, in this day and age of "hooking up" (and, in my day, of "free love" pre-AIDS), to forget that while the hunt is exciting, it ends with something that does not survive it.....
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Modes of Pleasure II

Modes of Pleasure

New face, strange face, for my unrest.
I hunt our look, and lust marks time
Dark in his doubtful uniform,
Preparing once more for the test.

You do not know you are observed:
Apart, contained, you wait on chance,
Or seem to, till your callous glance
Meets mine, as callous and reserved.

And as it does we recognize
That sharing an anticipation
Amounts to a collaboration –
A warm game for a warmer prize.

Yet when I’ve had you once or twice
I may not want you any more:
A single night is plenty for
Every magnanimous device.

Why should that matter? Why pretend
Love must accompany erection?
This is a momentary affection,
A curiosity bound to end,

Which as good-humoured muscle may
Against the muscle try its strength
- Exhausted into sleep at length –
And will not last long into day.
                                                                    Thom Gunn - American