But this flies in the face of what mathematics is all about! The whole point of our mathematical heritage and training is that we do not bow down to the authority of some obscure rules that we can never hope to understand. We must see–at least in principle – that each step in an argument can be reduced to something simple and obvious. Mathematical truth is not a horrendously complicated dogma whose validity is beyond our comprehension. It is something built up from such simple and obvious ingredients -and when we comprehend them, their truth is clear and agreed by all.