Unfortunately, if we get a message from extraterrestrials, we cant count on them laying out direct translations between one of their languages and, say, English or Swahili. And that, say anthropologist Ben Finney and historian Jerry Bentley, could limit how much we can learn from extraterrestrials. While we may be able to understand basic mathematics and astronomy, once extraterrestrials begin to describe their cultures, interstellar comprehension may suffer considerably. If fact, Finney and Bentley point out that early successes in decoding scientific parts of an extraterrestrial message might actually stand in the way of understanding more culturally-specific parts of the message.

As an analogy, they note that when European scholars began decoding ancient Maya hieroglyphs, their earliest successes were in understanding the basic numbering system used by the Maya, as well as their calendar systems, which were based on the visible motions of the Moon and Sun. In short, math and science provided the foundation for communication, just as many SETI scientists have predicted will be the case for interstellar communication.

This success in making sense of part of the Maya glyphs reinforced an idea that had been around among European scholars for centuries, going back to ancient Greek hopes that hieroglyphics from the Old Worldfrom Egypt, to be precisehad the power to represent ideas directly, and thus escape some of the messiness of spoken language.

The view that complex ideas could be shown directly through symbols can be traced back at least as far as Plotinus, an Egyptian-born Roman philosopher who followed the path of Plato. In Platos philosophy, the bedrock of reality is not in the things that we can see with our eyes and feel with our hands. Instead, ultimate reality consists of underlying "ideas" that serve as the blueprints for the material world. And Plotinus thought that Egyptian hieroglyphs offered a way to symbolize these ideas directly, without the intermediary of merely human languages. As author Maurice Pope summarizes Plotinus view of Egyptian hieroglyphs, "Each separate sign is in itself a piece of knowledge, a piece of wisdom, a piece of reality, immediately present."

As it turns out, Plotinus was wrong. But he was in good company.

For centuries, most eminent Egyptologists agreed with Plotinus. They dismissed the possibility that hieroglyphs could represent something as mundane as spoken language. But in the 1820s, French linguist Jean-Francois Champollion used the Rosetta Stone to draw parallels between the as-yet undeciphered Egyptian hieroglyphics and both well-understood Greek and a form of Egyptian script used widely in business transactions. As a result, Champollion was able to show that hieroglyphics often do represent sounds, much like other languages. Though Plotinus dream was broken, so too was the mystery of Egyptian hieroglyphics.

SETI scientists can learn an important lesson from the history of decoding hieroglyphics. Initial assumptions about the nature of the message can lead us astrayespecially when those assumptions help us decode parts of the message. While its true that some of the Mayan characters refer directly to numbers and months, the vast majority doesnt. The key then to decoding ancient hieroglyphics, and perhaps also messages from extraterrestrials, is to keep open to new possibilities, even if they seem to contradict initial successes.