Rousseau created fantastic worlds filled with odd juxtapositions, though his imaginary jungles were based on first-hand observation of the lush vegetation at the Jardin des Plantes in Paris. He probably transferred his sketches onto the canvas using a pantograph (a simple copying device), but then reworked and exaggerated them so that the horticultural varieties can no longer be precisely identified. He freely mixed flora and fauna from different environments and used the jungle vegetation as a decorative motif, covering large areas of his canvas with a dense pattern that verged on abstraction. Rousseau was similarly unrestrained in his merging of the human and animal worlds, giving monkeys and other primates such props as a milk bottle, back scratchers, and fishing rods.
The Dream, which depicts a nude woman lounging on a divan in the middle of the jungle, represents the pinnacle of Rousseau's achievement. With this work the artist brought together the studio (the sofa is modeled after the one in his own studio) and the jungle, the domestic and the exotic, and earned the respect of the avant-garde artists. They may also have admired the allover precision of the painting, in which each component—the reclining nude, the wide-eyed lions, the abundant greenery—is rendered with equal weight. As the poet and critic Guillaume Apollinaire wrote, "The picture radiates beauty, that is indisputable. I believe nobody will laugh this year."