When Wordsworth notes his faith that "every flower / Enjoys the air it breathes," or when Keats describes an unseen nightingale pouring forth its "soul abroad / In such an ecstasy," we may be inclined to classify these lyrical claims as Romantic hyperbole, rhetorically suspect forms of anthropomorphism, overly sentimental and poetically overblown. Likewise, when Wordsworth's heart fills "with pleasure" at the sight of daffodils, or when Blake says "How do you know but ev'ry Bird that cuts the airy way, / Is an immense world of delight," we may think that the poet is protesting too little or offering too much credit to the natural world for what is, in fact, a strictly "human" emotion. In this essay I will examine Romantic claims about pleasure in the natural world and pleasure derived from the natural world in terms of the "science" of the century before Darwin's On the Origin of Species, particularly the science of animate nature, the belief that all living things (and perhaps even "nonliving" things) were connected by a force that could be described, at least partly, in terms of the natural ability to please or to be pleased. I will conclude with a reflection on connections between the method of observational science in the Romantic period, the writing of poetry, and the sources of pleasure.