The Daily Telegraph reported in 2014 that Dali later explained that his aim was to represent how he existed in the bottom of the sea of subconciousness. He was giving a lecture at the event, during the course of which he began to suffocate. The helmet had to be prised off his head using the billiard cue that he also happened to be carrying.
When I set this question I was convinced that there was a famous photograph of Dali in the diving suit, and I'm sure I saw it at the time. But I'm now unable to find it on the Internet; the most-used photograph is the one used by The Guardian.
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