This is a revisit of a radical theory of cometary panspermia and cosmic life that was first proposed by Chandra Wickramasinghe and the late Sir Fred Hoyle in 1982. In its earliest form the theory of cosmic life started off as a speculation in 1974 after the first discovery of complex organic molecules and polymeric dust in interstellar space. The speculation soon developed into a serious scientific theory, predictions of which were available to be verified or falsified. Over four decades there have been a multitude of tests and predictions of the theory being positive in vindicating the proposition of life as a cosmic rather than a purely terrestrial phenomenon. A paradigm shift of enormous magnitude and significance is to be expected.The ideas and theories described in this book would have a far-reaching influence affecting the future development of diverse branches of science.