A reflection on the excellent documentary "Dangerous Knowledge", from BBC Channel 4 (2007).https://www.dailymotion.com/video/xdoe8uWe'll look at the presentaion of four great thinkers and mathematicians: Georg Cantor, Ludwig Boltzmann, Kurt Gödel and Alan Turing - and then view the changes in both Science and the Viennese culture and society of the early 19 hundreds in light of the nature of the brain hemispheres, and the cosmology of Dante's Divine Comedy.Thanks for listening!