A Beauty Cold and Austere

When I finished this game, in 3 not-long-enough sittings, I had the feeling that I had once again put yet another great IF game under my hat. And it's one of those of which I can truly say that I learned some very interesting things. I may be biased, because I have a background in mathematics and enjoy solving problems in math and physics, but I think this game also entertains--and enlightens--the math lay-person.
The game takes the player through mathematics in history, beginning with the ancient world, and the player advances by solving puzzles pertaining to the major discoveries. The player actually meets some of the historical personalities involved and learns something of their work.
I'm going to leave off discussing many of the particulars, because I feel like I would be spoiling it for the reader, but I really enjoyed how the game seemed to show, symbolically, how mathematics lies at the very root of existence, as a fundamental part of the universe. Also, if you have a keen eye for math humor, you'll find plenty of such references in ABCA.(Spoiler - click to show)Some examples--the log table, which is an actual table made of logs (if have used logarithms in math, you'll spot this one); the square root, which actually is a square made from a root; one puzzle involved Descartes's famous saying 'I think, therefore I am.'--reminding me of a puzzle in my own game 'Bullhockey!'; an 'empty set'--your holdall; even the game's initials seem to allude to a triangle in trigonometry, made by segments ABCA etc, etc.
I really don't have any real complaints about this game. The closest I can come to one is--(Spoiler - click to show)this game has a number of levels, each of which has a central room, from which there are a number of exits--not all of which may be obvious or usable at first. The more you advance on a level, the more 'clear' this central room becomes, and the more exits open up, plus at one point, an exit to the next level opens. I didn't realize this at first, I felt a bit dogged when the room seemed to change on subsequent visits. But this isn't really a complaint--there is a logical reason why this would happen and the player will figure it out.
I think that ABCA is well-suited for being part of a course in the history of mathematics, and I wouldn't be surprised if it indeed is. I honestly think that if a student who balks at taking a math course played this game, s/he would want to learn more about math as a result.