Suppose a dog, overcome with weakness & hunger, were to come across a slaughterhouse, and there a dexterous butcher or butcher’s apprentice were to fling him a chain of bones — thoroughly scraped, without any flesh, smeared with blood. What do you think: Would the dog, gnawing on that chain of bones — thoroughly scraped, without any flesh, smeared with blood — appease its weakness & hunger?
No, lord. And why is that? Because the chain of bones is thoroughly scraped, without any flesh, & smeared with blood. The dog would get nothing but its share of weariness & vexation.
In the same way, householder, a disciple of the noble ones considers this point: ‘The Blessed One has compared sensuality to a chain of bones, of much stress, much despair, & greater drawbacks.’ Seeing this with right discernment, as it actually is, then avoiding the equanimity coming from multiplicity, dependent on multiplicity, he develops the equanimity coming from singleness, dependent on singleness, where sustenance/clinging for the baits of the world ceases without trace.
This reflection is from Handful of Leaves, Volume II, Majjhima Nikaya 54, Potaliya Sutta, (pdf) p. 371.