There's nothing egotistical about it Set. Fermi didn't think things would come here because they knew about us, he reasoned they would be here just because the swarm would have sufficient density within a certain period of time. It was math, not ego. Granted he was making a series of assumptions, but each one seemed logical. And to this day nobody has answered the paradox effectively. I suggest that before you go off on a tiff about childish conceit, you do a little background on the subject. I expect thoughtless bullshit from Spendi, but I expect better from you. You do your research on other subjects, and I respect what you have to say, but you're not impressing me with your thoughtfulness on this subject so far.
Yes, this does make a series of assumptions, and the core assumptions are seriously flawed. I did not go off on a tiff, and that's a rhetorical device i would not have thought you would use. I'm amused at this thesis, but not angry about.
This thesis assumes for example, that technological civilizations would be monolithic socially and politically, because i assure you, that in order to colonize, you're going to need huge energy expenditures to transport colonists and their necessary life-support, even if one could have perfected supsended animation of the colonists. Our one example of a sentient, technologically-sophisticated species offers not reason to believe that technologically-sophisticated species can be expected to produce a unitary civilization on a single planet, never mind on several planets.
If a civilization were space-faring, then we'd want to have a plausible reason for them to colonize other planets. The most obvious reason for this would be for more living space and resources. If that were the goal, even were there a planetarily-unitary (just made that up, and don't know if "planetarily is a word--the spellchecker doesn't think so) society, the enormous energy expenditure to leave the mother-well (speaking of the gravitational well of the home planet) with colonists, and all the resources necessary to support them on a long voyage at a modest fraction of light-speed, even with suspended animation, strongly suggests that they would colonize the nearest plausible planets--which might even entail "terra-forming" (in their own planetary terms) of other planets in their system.
Which leads us back to the problem that our star and planet are in the galactic boonies--so once again, why would anyone have come here? Every plausible mathematical estimate which i have seen, ignoring the gross assumptions entailed, reach the conclusion that there may be tens of thousands of technologically-sophisticated societies--which means that even with a concerted division of labor, they'd have millions, even tens of millions, of star systems to explore. Fermi and company, for all of their mathematical and scientific expertise, are almost embarrassingly naive in political and social terms.
Our experience is that species unity is difficult, if not actually impossible of attainment. Our experience suggests that only great resource wealth combined with strikingly important motivation lead to huge technological projects (the Manhattan Project was spurred by the possibility that the Nazis were working on an atomic bomb--it was not product of free research with unlimited funds; the space race was motivated by the undoubtable evidence that the Russians had prefected intercontinental ballistic missiles which could operate in space--Sputnik proved it, and for all the glamour and hooplah of NASA, the motivation was military threat--not the egocentrism of demonstrating the excellence of our system). Our experience suggests to us that technological civilizations can only be organized politically, and that politically effective systems function through compromise--settling for second- or even third-best is usually how large social and political projects get accomplished.
Fermi and company do not factor into their calculations the probabilities of a unitary civilization arising which spans the entire cradle planet of the species. Their calculations do not factor the probability that technologically sophisticated civilizations may stagnate or even destroy themselves before reaching a level of sophistication necessary to engage in interstallar colonization. Their calculations do not take into consideration the myriad competing claims on a civilization which is the consequence of intelligent individualism--and our experience on this planet is that civilizations which do not encourage individual enterprise and research are likely to stagnate, and become the prey of vigorous barbarians.
The estimates to which you refer fail to account for a host of social and political factors which act upon civilizations--and which our experience over thousands of years (literally) show transcend culture. I consider the thesis naive because it fails to take into consideration what would pass for the equivalent of "human nature" in the putative sentient, technologically-sophisticated species.
Before the Great War, the brilliant German military planner, von Schlieffen, wrote an operational plan for invading France, via Belgium, and taking Paris within five weeks. But von Schlieffen failed to take into account simple facts of human nature--his deployments were not used exactly as planned, because of the politics of the Prussians dealing with the Bavarians; his planned assumed (as almost all Europe assumed) that the Russians would require six weeks to mobilize and set their armies in motion--the Russians promised the French (who didn't believe it) that they would mobilize and invade East Prussia within three weeks, but they were wrong, they did it in two weeks; von Schlieffen's plan assumed the English could be brushed aside, but they weren't. Finally, von Schlieffen's plan took absolutely no account for human frailty--German junior officers were drunk almost every day after the second week, because they were losing so much sleep, that they constantly drank coffee, and then chased it with wine or hard liquor, trying to keep awake and take the edge off. German soldiers were so fatigued after four weeks, that the French had to wake them up to make captives of them, and often unable to accomplish that, loaded them into trucks while they slept through the entire capture.
I don't suggest that the two cases are parallel, but i do wish to point out that the estimates, and the claims about colonization, ignore the realities of what it means to deal with billions of sentient, intelligent individuals in the aggregate. There are too many assumptions, and too many of them which ignore "human nature" (the equivalent of which can be assumed to exist in other species as or more intelligent than are we) for them to be plausible to me.