Srimad Bhagavatam Canto 11, Chapter 22, Text 56

SB 11.22.56

arthe hy avidyamane ’pi
 samsrtir na nivartate
dhyayato visayan asya
 svapne ’narthagamo yatha
 
Translation: 
 
For one who is meditating on sense gratification, material life, although lacking factual existence, does not go away, just as the unpleasant experiences of a dream do not.
 
Purport: 
 
One may object that if Lord Krsna insists that material life is false, then why should one endeavor to stop it? The Lord therefore explains here that although not factual, material life stubbornly continues for one addicted to sense gratification, just as a frightening dream continues for one merged in sleep. The word avidyamana, “not existing,” means that material life is based on mental concoction, in which one thinks, “I am a man,” “I am a woman,” “I am a doctor,” “I am a senator,” “I am a street sweeper” and so on. A conditioned soul enthusiastically performs his activities based on the imaginary identification with the body. Thus although the spirit soul exists and the body exists, the false identification with the body does not exist. Material life, based on a false idea, has no factual existence.
 
After one awakens from a dream, the dim reflection of the dream may linger in one’s memory. Similarly, one engaging in the devotional service of the Lord may be troubled sometimes by the dim reflection of sinful life. One should therefore become strong in Krsna consciousness by hearing the Lord’s instructions to Sri Uddhava.
Srimad Bhagavatam Canto 11, Chapter 22, Text 54-55
Srimad Bhagavatam Canto 11, Chapter 22, Text 57