I thought this extract from 'All quiet on the Western Front', written by Erich Maria Remarque in 1919, is appropriate for this thread:
'The soldier is on friendlier terms than other men with his stomach and intestines. Three-quarters of his vocabulary is derived from these regions, and they give an intimate flavour to expressions of his greatest joy as well as of his deepest indignation. It is impossible to express oneself in any other way so clearly and so pithily. Our families and our teachers will be shocked when we go home, but here it is the universal language.'