William Paley was an eighteenth-century theologian who published, in 1802, a treatise entitled Natural Theology - or Evidences of the Existence and Attributes of the Deity Collected from the Appearances of Nature. In this treatise Paley incorporates the best biological scholarship of his day to describe, with beautiful and reverent descriptions, the dissected machinery of life. His best example is the description of the human eye as a carefully designed optical instrument, and he concludes that, just as the telescope is an instrument designed to aid the eye in looking at distant objects, so too is the eye. Both instruments must have had an intelligent designer.