Bailyn, Charles. ASTR 160: Frontiers and Controversies in Astrophysics, Spring 2007. Yale OpenCourseWare: Astronomy, Accessed 23/9/14 http://oyc.yale.edu/astronomy/astr-160/lecture-24 License: Creative Commons Attribution-Noncommercial-Share Alike 3.0 license Professor Bailyn begins the class with a discussion of a recent New York Times article about the discovery of a new, earth-like planet. He then discusses concepts such as epicycles, dark energy and dark matter; imaginary ideas invented to explain 96% of the universe. The Anthropic Principle is introduced and the possibility of the multiverse is addressed. Finally, biological arguments are put forth for how complexity occurs on a cosmological scale. The lecture and course conclude with a discussion on the fine differences between science and philosophy.