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273 thought that it was fair to ask what might motivate extraterrestrials to “reach out and touch someone.” If there is no reason for them to do so, we may never discern their existence.” What forces favor interstellar communication? Goldsmith and Owen proposed curiosity, gregariousness, and what might be called social avarice—the hope of obtaining valuable information. Forces that oppose communication include fear, inertia, and the press of other priorities.” To have a reasonable chance of making themselves known by radio, extraterrestrials must have not only the ability to communicate but also the desire. A sustained transmission effort could require significant resources; the listeners too would have to make a long-term commitment. Oliver acknowledged that the whole thing depends on the longevity and effectiveness of the communication effort at both ends.” Many SETI advocates assume that the technologically superior civiliza- ion would bear the onus of initiating contact by transmitting, because that civilization can do it more easily. As Jill Tarter explained, transmitting is a much harder job than listening, so we put the burden of transmission on he older technologies. If there are no older technologies, our searches will not succeed. The average civilization’s lifetime as a seeker after contact may be far ess that the average civilization’s lifetime with communications ability. There must be some limit to how long a civilization will continue to try to communicate with hypothetical others. Von Hoerner’s estimate of the average length of communication time was 6500 years.“ Although long by he standards of twenty-first-century Earth, this is but a brief moment in galactic history. At any given time in that history, only a small percentage of technological civilizations may broadcast signals in the hope that they will provoke responses. We still have to ask why. If the aliens’ motive for communication is self- interested, Regis pointed out, then they are seeking to benefit from contact with societies more advanced than their own just as SETI advocates on Earth are. Exchanging information with emerging technical civilizations like ours may be a much lower priority.” The classic SETI paradigm treats interstellar communication as the apex of cultural evolution among technological civilizations. However, no phase of cultural evolution is final. What might lie beyond exchanging messages? There may be a more civilized way of life than a communicative one. Legends In the standard SETI paradigm, a civilization that is near to us in space is going to be very far from us in time; any random one would be very old. Sagan and Newman thought it possible that our Galaxy is teeming with civilizations as far beyond our level as we are beyond the ants, and paying us about as much attention as we pay to ants. They Want to Communicate