The Aztecs had more numbers than we do, or at least symbols denoting numerical concepts. When it came to measuring land—critical for levying the proper tax or tribute—these medieval Mesoamericans used arrows, hearts, hands and other units representing fractions, according to a new study in Science.
To figure this out, mathematician Maria del Carmen Jorge y Jorge of the National Autonomous University of Mexico (U.N.A.M) channeled the mind of an Aztec land surveyor. That meant retraining herself to use a different numerical system and combing through the Codex Vergara, one of two remaining books that record Aztec land surveying.
Working with geographer Barbara Williams and del Carmen Jorge y Jorge counted 367 fields in this book with both an overall area for the plot of land as well as the lengths of the sides. Roughly 60 percent of these fields had areas that matched the basic mathematical rule of length multiplied by width or other common surveying calculations.
Also at Nat. Geo with this quote:
"I think [the study] is neat because it shows that this sort of math and science was pretty practical in orientation," said Michael Smith, an archaeologist and Aztec expert at Arizona State University.
"We have the idea that ancient societies were dominated by religion. Yeah, religion was important, but they were also very practical people doing very practical things," Smith said.
This is an interesting topic, IMO: Where did this idea that ancient peoples were "all about religion" come from? I've seen side discussions of it in various places, but I don't remember any extended treatises on the source. For whatever reason, the Maya and Egypt are the archetypal Total Religious Societies. In the latter, a somewhat empirical case can be made for it since they had such a tremendous building and epigraphic program devoted to the afterlife, an explicitly religious topic.
My gut feeling is that Egypt more or less set the program for interpreting ancient societies as hyper-religious. So when people started looking at the Maya they immediately saw pyramids and made the connection. OTOH, maybe the Egyptian case was already conditioned by Romanticism that saw the primitive as being bound up in the non-rational.