Many prestigious thinkers have given the Gifford Lectures over the years, and as they are intended to be about natural theology broadly conceived, they often have to do with science and religion, philosophy, theology, etc. At their website they list all of the lecture series that have been given, going back to the late 19th century, and many of the older ones are available to read online. Since the lectures have usually been picked up for publication, they are (I assume) in their original form before having been rewritten, which can be either good or bad depending on your perspective. Many of the more recent lectures cannot be read online for (again, I assume) copyright issues, but you can still read an impressive number of important works there, such as The Varieties of Religious Experience by William James; The World and the Individual (vol. 1 and vol. 2) by Josiah Royce; Space, Time and Deity (vol. 1 and vol. 2) by Samuel Alexander; The Nature of the Physical World by Arthur Eddington; and The Mystery of Being (vol. 1 and vol. 2) by Gabriel Marcel. More recent lecture series include The Evolution of the Soul by Richard Swinburne; In Search of Deity by John Macquarrie; and Warrant: The Current Debate by Alvin Plantinga. Again, these are just those that are available to read online at their website. Their list of important authors whose lectures are not online is obviously more extensive.
(cross-posted at Agent Intellect)
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