Speaking of mind blowing... I took ketamine for the first time a few months ago (by prescription from a psychiatrist, yada yada yada). I have just come back to normal from a ketamine trip during which I constantly kept thinking about what you've said. In fact, I was thinking about it so much that I couldn't relax enough to get the full effect of the ketamine. For me, the first thing that lets me know that the ketamine is kicking in is that I become able to "see" even though my eyes are closed. I remain aware that I'm sitting in my living room and wearing a blindfold, but in my mind there are patterns that I can look at and think "Ooh that's pretty." Not just the abstract sensation of seeing a pretty pattern, but actually an experience like vision, complete with the ability to look at a different part of the pattern and see something new. When I stop being able to do that, I know that the ketamine has worn off.

I thought that that's what people called hallucinating, which seemed odd to me since I never felt like what I was seeing in my mind was real, whereas people say that hallucinations can seem real. Now I wonder - can some other people, like you, just see things in their mind that way all the time? Amazing!

I don't mean to imply that I think your experience of the world is the same as mine is on ketamine, since ketamine does a lot more than let me look at pretty patterns. The first time I took it, I was sad since I realized that I was all that existed and the entire world was a figment of my imagination, a dream that I woke from. But being able to look at things in my mind has been beautiful and very dramatically different from the way my brain works without ketamine. So far I've only seen patterns like twinkling lights, clouds, or mazes. You're saying that you can see anything you want... Excuse me because I'm going to say something immature: if I could see things in my mind like that, then it would take me a really long time (if ever) to get tired of just seeing naked ladies.

But if I really have aphantasia, how is it that I've always been good at "using my imagination"? I love reading fantasy novels and they're not just words on a page for me. And how do I solve geometry problems in my mind? I'm better than most people at geometry. Strange.