By this he meant that myth transforms concepts into beings and stories. In Müller's view, "gods" began as words constructed to express abstract ideas, but were transformed into imagined personalities. Thus the Indo-European father-god appears under various names: Zeus, Jupiter, Dyaus Pita. For Müller all these names can be traced to the word "Dyaus", which he understood to imply "shining" or "radiance". This leads to the terms "deva", "deus", "theos" as generic terms for a god, and to the names "Zeus" and "Jupiter" (derived from deus-pater). In this way a metaphor becomes personified and ossified. This aspect of Müller's thinking was later explored similarly by Nietzsche. Gifford Lectures In 1888, Müller was appointed Gifford Lecturer at the University of Glasgow. These Gifford Lectures were the first in an annual series, given at several Scottish universities, that has continued to the present day. Over the next four years, Müller gave four series of lectures. The titles and order of the lectures were as follows: Natural Religion. This first course of lectures was intended as purely introductory, and had for its object a definition of Natural Religion in its widest sense. Physical Religion. This second course of lectures was intended to show how different nations had arrived at a belief in something infinite behind the finite, in something invisible behind the visible, in many unseen agents or gods of nature, until they reached a belief in one god above all those gods. In short, a history of the discovery of the infinite in nature. Anthropological Religion. This third course was intended to show how different nations arrived at a belief in a soul, how they named its various faculties, and what they imagined about its fate after death. Theosophy or Psychological Religion. The fourth and last course of lectures was intended to examine the relation between God and the soul ("these two Infinites"), including the ideas that some of the principal nations of the world have formed concerning this relation. Real religion, Müller asserted, is founded on a true perception of the relation of the soul to God and of God to the soul; Müller wanted to prove that this was true, not only as a postulate, but as an historical fact. The original title of the lectures was 'Psychological Religion' but Müller felt compelled to add 'Theosophy' to it. Müller's final Gifford Lecture is significant in interpreting his work broadly, as