"If one does not know whether a system “as a whole” (in contrast to certain features of it) is good or bad, the safest “policy conclusion” is to “muddle through” – either with it, if one has long lived with it, or without it, if one has lived without it... If we did not have a patent system, it would be irresponsible, on the basis of our present knowledge of its economic consequences, to recommend instituting one. But since we have had a patent system for a long time, it would be irresponsible, on the basis of our present knowledge, to recommend abolishing it. This last statement refers to a country such as the United States of America – not to a small country and not a predominantly nonindustrial country, where a different weight of argument might well suggest another conclusion..."