It may have to do with complexity. The Kolmogoroff complexity or entropy of a system roughly scales with the area bounding that system, and any IGUS that begins to control that sort of hypertechnology must manage that sort of complexity. Most likely they evolved like us with neuro-networks adapted from some natural condition and eventually as they progress they find they can no longer manage things. Their situation implodes. I suspect our situation will implode this century. As for von Neumann probes, these will over time evolve to form potentially a sort of "galactic bacteria." They may simply not evolve in most cases to engage in massive programs. It may be more to their advantage to stay small and take advantage of the sparse resources available by being conservative. LC -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to firstname.lastname@example.org. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.