George Harrison: These books are such a lot of work. I don't know how he did it all.
Gurudasa: While everyone else sleeps, Prabhupada...
George Harrison: Yes.
Prabhupada: At night I don't sleep. Not that because I am nowadays sick. But generally I don't sleep. At most two hours. At most.
Hari-sauri: I think it's a long time since you've taken any rest at night.
Prabhupada: I take little rest during daytime. So on the whole, three to four hours. But actually I do not like to sleep.
George Harrison: No, it's a waste of time.
Prabhupada: I think it is, when I go to sleep, I think that now I'm going to waste my time. I actually think like that.
George Harrison: What's the word for..., the call it a little, little death. Sleep is the little death.
Prabhupada: The sastra also, Prahlada Maharaja describes the sleeping is waste of time. You find out that verse.
Hari-sauri: It's in Seven, Two?
Prabhupada: Seventh Canto. He's estimating you have got hundred years at most. Out of that, fifty years lost, sleep. And then twenty years playing as child, a boy. And in old age, another...
Hari-sauri:

                    pumso varsa-satam hy ayus
                     tad-ardham cajitatmanah
                    nisphalam yad asau ratryam
                    sete 'ndham prapitas tamah

   "Every human being has a maximum duration of life of one hundred years, but for one who cannot control his senses, half of those years are completely lost because at night he sleeps twelve hours, being covered by ignorance. Therefore such a person has a lifetime of only fifty years."
Prabhupada: Fifty years immediately minus. Then out of the fifty years?

[Srila Prabhupada Conversation with George Harrison, July 26, 1976, London]