 But whether magic is viewed negatively or positively the substance of it as a practice can be drawn out.That is, that magic was a practice aimed at trying to locate and control the secret forces of the cosmos, and the sympathies and antipathies that were seen to make up these forces.The "Natural History" of Pliny the Elder (CE 23/24-79) is a voluminous survey of knowledge of the late Hellenistic era, based according to Pliny on a hundred or so earlier authorities.