Oh the misuses which are made of this word _science_! Once these misuses were the monopoly of metaphysics, to whose despotic nature they appeared suitable. And the strangest instances could be quoted, even from great philosophers, from Hegel, from Schopenhauer, from Rosmini, which would show how the humblest practical conclusions, made by the passions and interests of men, have often been metaphysically transformed into inferences from the Spirit, from the Divine Being, from the Nature of things, from the finality of the universe. Metaphysics hypostatised what it then triumphantly inferred. The youthful Marx wittily discovered in the Hegelianism of Bruno Bauer, the _pre-established harmony of critical analysis_ (Kritische Kritik) under German _censorship_. Those who most frequently have the word in their mouths make a sort of Sibyl or Pythia of a limited intellectual function. But the _desirable_ is not science, nor is the practicable.[61] Is scientific knowledge then in fact superfluous in practical questions? Are we to assent to this absurdity? The attentive reader will be well aware that we are not here discussing the _utility_ of science, but the possibility of _inferring_, as some claim to do, _practical programmes from scientific prepositions_; and it is this possibility only which is denied. Science, in so far as it consists in knowledge of the laws governing actual facts, may be a legitimate means of simplifying problems, making it possible to distinguish in them what can be scientifically ascertained from what can only be partially known. A great number of things which are commonly disputed, may be cleared up and accurately decided by this method. To give an example, when Marx in opposition to Proudhon and his English predecessors (Bray, Gray, etc.) showed the absurdity of creating _labour bonds_, _i.e._ labour-money; and when Engels directed similar criticisms against Dühring, and then again, perhaps with less justification, against Rodbertus[62] or when both established the close connection between the method of production and the method of distribution, they were working in the field proper to scientific demonstration, trying to prove an inconsistency between the conclusions and the premisses, _i.e._ an internal contradiction in the concepts criticised. The same may be said of the proof, carefully worked out by the free traders, of the proposition: that protection of every kind is equivalent to a destruction of wealth. And if it were possible to establish accurately that law of the tendency of the rate of profits to decline, with which Marx meant to correct and widen the Ricardian law deduced from the continuous encroachments of the rent of land, it could be said, _under certain conditions_, that the end of the bourgeois capitalist organisation was a scientific certainty, though it would remain doubtful what could take its place.