Although we often ponder the possible otherworldly morphology of extraterrestrials, a harder exercise is conceiving alien intelligences.
An alien might have four limbs, just like we humans. Or it might sport 17 tentacles, depending on evolutionary pressures. We can observe, quantify and describe such things. But how can we truly gauge the workings of an alien mind?
A new paper, publishing in Acta Astronautica in February, offers a preliminary exercise meant to get us to think outside our own box in assessing alien intellect. The exercise is called COMPLEX, which stands for "COmplexity of Markers for Profiling Life in EXobiology." The project compares various non-human intelligences—including animals, microbes and machines—to each other (rather than humans) and across several categories of behavior and mental capability.