Suppose that men, otherwise intelligent, should be mistaken on any point whatever of natural history for many centuries, that would signify or prove nothing.

Would water, air, earth, fire, be less useful to man whether they were or were not elements?
Such errors are of no consequence; they lead to no revolutions, do not unsettle the mind; above all, they injure no interests, so they might, without inconvenience, endure for millions of years.

The physical world would progress just as if they did not exist.

Would it be thus with errors which attack the moral world?
Can we conceive that a system of government, absolutely false, consequently injurious, could be carried out through many centuries, among many nations, with the general consent of educated men?
Can we explain how such a system could be reconciled with the ever-increasing prosperity of nations?
You acknowledge that the argument you combat ought to make a profound impression.

Yes, truly, and this impression remains, for you have rather strengthened than destroyed it." Or again, they say: "It was only in the middle of the last century, the eighteenth century, in which all subjects, all principles, without exception, were delivered up to public discussion, that these furnishers of speculative ideas which are applied to everything without being applicable to anything--commenced writing on political economy.