"For instance, on the planet Earth, man had always assumed that he was more intelligent than dolphins because he had achieved so much --- the wheel, New York, wars, and so on --- whilst all the dolphins had ever done was muck about in the water having a good time. But conversely, the dolphins had always believed that they were far more intelligent than man --- for precisely the same reasons."
Yeah sure. If they had the ability to learn math but chose not to, it might be true. They don't, though - and I bet there is more than a few dolphins that'd like to do more if they could.
"For instance, on the planet Earth, man had always assumed that he was more intelligent than dolphins because he had achieved so much --- the wheel, New York, wars, and so on --- whilst all the dolphins had ever done was muck about in the water having a good time. But conversely, the dolphins had always believed that they were far more intelligent than man --- for precisely the same reasons."