Re: Alien Communication Re: Ethics of being a Creator

Eugene Leitl (
Thu, 30 Apr 1998 12:51:00 +0400 (MSD)

Paul Hughes writes:
> Scott Badger wrote:
> Again, studies of cetaceans have show that their sonar 'vision' is as acute as
> our optical vision. Not only that, because of the nature of sound, they can

Uh, that would seem unlikely, give the wavelength of ultrasonic sound
in water vs. our vision system operates hard at the physical threshold
for optical instruments. The resolution of long-range sonar whales
should be pretty lousy, though far ranging.

> 'see' through many of the objects they bounce sounds off. This give them a
> unique kind of 3-d hologaphic perception of the world around them.

Inasmuch would this differ from you internal scene representation? You
have textures, depthcueing and stereo to construct a 3d description.

The interesting part of sonar vision is that you can tell materials
with different sound propagation velocities apart, e.g. a plastic and
a steel ball. Also, you could theoretically share a mental image,
though there is no evidence that the cetaceans really do that.

> Paul


P.S. Is the extropy listserv malfunctioning, or is this just me?