I now realize that years ago I watched Power RAngers with my young son, and guess what? The transformers (see below) looked a bit like Boccioni sculptures? He was way ahead of his time and a genius in my eyes...
Arp told the story of how, when he was notified to report to the German consulate, he avoided being drafted into the German Army: he took the paperwork he had been given and, in the first blank, wrote the date. He then wrote the date in every other space as well, then drew a line beneath them and carefully added them up.
He then took off all his clothes and went to hand in his paperwork.