The Buddha defined this "dream world" with more specific terms:
"The Blessed One said: "Monks, sensuality is inconstant, hollow, vain, deceptive. It is illusory, the babble of fools. Sensuality here & now; sensuality in lives to come; sensual perceptions here & now; sensual perceptions in lives to come: both are Mara's realm, Mara's domain, Mara's bait, Mara's range. They lead to these evil, unskillful mental states: greed, ill will, & contentiousness. They arise for the obstruction of a disciple of the noble ones here in training."
~~ http://www.accesstoinsight.org/tipitaka ... .than.html