More on Gaudí's Cathedral, a River on Fire, and the Brain Game That Cuts Dementia Risk

Plus: the horse walked away and another optical illusion, history of the heart symbol, memories of children playing on Tyneside pavements in the 1960s

I want to start by thanking the new paying subscribers; this experiment is working because you are making it work with your support, your questions, your comments, and the way you talk to each other. More has become a community faster than any newsletter I have built before.

This week, you asked me to name the brain training program I wrote about in Dayb…