Andrew Stacey (he/him)

@noneuclideandreamer@mathstodon.xyz First two look good. For the third, the shaded base is a bit odd. The stereograms that I'm used to don't have filled regions - it's hard to track between the eyes. I don't think the fourth works. I think the sides mean that the "trick" is revealed, and the lack of other clues breaks the 3d illusion.

@gwenbeads I suspected as much. He was a lovely person. I wouldn't say I knew him very well, but when I lived in Trondheim we got into the habit of having a coffee and a talk about maths whenever he visited the city. I was already inclined to buy your book. That just seals the deal.

@gwenbeads just checking names, was the Roger you mention Norwegian?

@ColinTheMathmo@mathstodon.xyz so that sounds like it rules out the first one, that 2+3 just "is" 5. Then which of the other two feels more like what you do when you hear "what is 2+3?"

@ColinTheMathmo@mathstodon.xyz interesting! If I'd asked about, say, 7-5 then how would you see that as "7-" applied to 5? I'm planning a blog post about the distinctions and wanted some data as to people's inclinations so all will be made plain soon!

@ColinTheMathmo@mathstodon.xyz as the official in charge of this poll, I consider your musings officially helpful!