Srimad Bhagavatam Canto 11, Chapter 13, Text 08

SB 11.13.8

sri-uddhava uvaca
vidanti martyah prayena
 visayan padam apadam
tathapi bhuñjate krsna
 tat katham sva-kharaja-vat
 
Translation: 
 
Sri Uddhava said: My dear Krsna, generally human beings know that material life brings great future unhappiness, and still they try to enjoy material life. My dear Lord, how can one in knowledge act just like a dog, an ass or a goat?
 
Purport: 
 
The standard methods of enjoyment in the material world are sex, money and false prestige, all of which are obtained with great suffering and eventually lost. One engaged in material life suffers in the present and has only a very bleak future to look forward to in the continuing cycle of birth and death. Thus, how can human beings who have seen these things and know them very well continue to enjoy life like dogs, asses and goats? Often a dog will approach a bitch for sex, but the lady dog may not be attracted and will show her teeth, snarl and threaten the poor dog with serious injury. Still he goes about his business trying to get a little sex pleasure. Similarly, many times a dog risks being beaten or shot while stealing some food in a place where he knows he should not go. The ass is very attracted to the she-ass, but the lady ass often kicks him in the legs. Similarly, the ass’s master gives the ass a handful of grass, which the poor ass could get anywhere, and then burdens him with great loads. The goat is generally raised for slaughter, and even when the goat is brought into the slaughterhouse he shamelessly goes after the lady goat to get sex pleasure. In this way, even at the risk of being shot, bitten, beaten and slaughtered, animals persist in their foolish sense gratification. How can an educated human being commit himself to such a condemned way of life, wherein the result is practically the same as that of the animals? If by cultivating the mode of goodness one’s life is filled with happiness, enlightenment and future rewards, why would anyone cultivate the modes of passion and ignorance? This is Uddhava’s question.
Srimad Bhagavatam Canto 11, Chapter 13, Text 07
Srimad Bhagavatam Canto 11, Chapter 13, Text 09-10