A great number of the things we depend on exist due to the influence of non-white cultures. I wish this was celebrated more. But the person who led the assembly on black inventors concentrated on inventions in the last 200 years, his claims weren't all that helpful in promoting the achievements of BAME inventors. There was a fantastic programme on the digit zero years ago. That's the sort of thing he should have been telling the kids - pointing out how many things require zeroes to work, such as computers, written subtraction (as a means of calculation, not just recording the event), long division etc. We wouldn't have got very far if we'd stuck with Roman numerals. Just as well ideas spread from other parts of the world, isn't it?