Daniel, debating an orthdox neo-classical economist about the virtues of the market is like discussing the infallibility of the pope with a Roman Catholic priest. Orthodox economics is the latter-days theology - true by definition and fiat, beyond the challenge of facts and reason. At least when you try to debate a priest, he will treat you as a soul in need of direction, which deserves some respect, whereas all you can expect from an economist is arrogance and condescention.
Economics is not science but legitimating mythology. Economics is perceived as science not because of the power of its explanations, which is nil, but because of pseudo-scientific rituals its proponents perform: the use of dense and incomprehensible jargon and obfuscation by esoteric mathematic formulas. But let's face it, the emperor has no clothes. When stripped of its jargon, neo-classical economic "theory" is nothing but a pathetic bunch of common-sense wisdom, such as "a drop in a bucket" or "better one bird in hand than two on a bush" ("marginal utility" "and "opportunity cost" translated into English).
The sole purpose of this pseudo-scientific witchcraft is to produce the aura of scientific plausibility to the propaganda line that capitalism is the best possible world - regardless of what people's actual experiences are. You cannot prove it wrong, because any counter-evidence or counter-argument is either declared irrelevant or contemptuously ignored by the economist cabal.
Perelman, and for that matter anyone challenging the economic orthodoxy, should expect the same treatment as any blasphemy gets from religious fundamentalists - rabbidly visicious denunciations. Responding to such denunciations is pointless, because no argument can sway this market fundamentalist crowd's faith. Reasoning with them is like the biblical throwing pearls before pigs. At least wasteful and pointless, sometimes even dangerous.
I such situations, debating is pointless and silence may be better than a thousand words, as in the following anecdote. Socrates once approached a sophist and asked him "who are you?" "I am a philosopher, cant' you see?" answered the sophist. "What is a philosopher?" queried Socrates. "A philsopher is someone whose wisdom is beyond comprehension of commoners, like you" replied the sophist. "Well, then" said Socrates, "the words of commoners like me should not affect your mind and feelings, should they?" When the sophist replied "That is correct," Socrates threw a few common insults at him. The sophist condescendingly ignored them and then emphaticaly asked "So, silly man, do you now believe that I am philosopher?" "I would" replied Socrates, "if you remained silent."
wojtek