Sanity

Giuseppe di Cattivo realised that no one could look upon his painting, The Abomination, without losing their sanity. (TV: Mona Lisa's Revenge)

The Fourth Doctor believed that Christmas lights "always end[ed] up in an impossible tangle that takes a month and most of your sanity to unpick", and he used this as an analogy to explain to Leela how the unrivalled cosmic storm known as the Great Desolatrix ripped through time and space. (PROSE: Red Planet)