> A certain amount of rationalism is a vital part of social science,
> including economics. Marx, at any rate, was certainly no empiricist.
These claims involve implicit ontological and anthropological premises. They aren't Marx's.
For him, that "reason governs the world" is discoverable "empirically" through a phenomenological (in Husserl's sense) interrogation of experience.
Thus he claims that:
"The premises from which we begin are not arbitrary ones, not dogmas, but real premises from which abstraction can only be made in the imagination. They are the real individuals, their activity and the material conditions under which they live, both those which they find already existing and those produced by their activity. These premises can thus be verified in a purely empirical way." <http://www.marxists.org/archive/marx/works/1845/german-ideology/ch01a.htm
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On this basis he claims it can be demonstrated that:
"Reason has always existed, but not always in a reasonable form. The critic can therefore start out from any form of theoretical and practical consciousness and from the forms peculiar to existing reality develop the true reality as its obligation and its final goal." <http://www.marxists.org/archive/marx/works/1843/letters/43_09.htm>
This is what he claims his "critique of political economy" accomplishes. It's an application of Hegel's "higher dialectic of the conception" to capitalism, an application that claims to show that capitalist "estrangement" - the substitution of "working capital" for "squandering wealth" - works to develop "mind" as expressed by the development of "productive forces" and "the integral development of every individual producer" to the degree necessary to enable these individuals to imagine and build a society from which all barriers to the full development and actualization of "mind" - i.e. of "reason" - have been removed.
Thus "the growing domination of capital" is "the estrangement which is growing and therefore hastening to its annulment. This is indeed the only way in which that which exists affirms its opposite." <http://www.marxists.org/archive/marx/works/1844/manuscripts/needs.htm>
"The outstanding achievement of Hegel’s Phänomenologie and of its final outcome, the dialectic of negativity as the moving and generating principle, is thus first that Hegel conceives the self- creation of man as a process, conceives objectification as loss of the object, as alienation and as transcendence of this alienation; that he thus grasps the essence of labour and comprehends objective man – true, because real man – as the outcome of man’s own labour. The real, active orientation of man to himself as a species-being, or his manifestation as a real species-being (i.e., as a human being), is only possible if he really brings out all his species-powers – something which in turn is only possible through the cooperative action of all of mankind, only as the result of history – and treats these powers as objects: and this, to begin with, is again only possible in the form of estrangement." <http://www.marx.org/archive/marx/works/1844/manuscripts/hegel.htm>
"The functions fulfilled by the capitalist are no more than the functions of capital - viz. the valorization of value by absorbing living labour - executed consciously and willingly. The capitalist functions only as personified capital, capital as a person, just as the worker is no more than labour personified. That labour is for him just effort and torment, whereas it belongs to the capitalist as a substance that creates and increases wealth, and in fact it is an element of capital, incorporated into it in the production process as its living, variable component. Hence the rule of the capitalist over the worker is the rule of things over man, of dead labour over the living, of the product over the producer. For the commodities that become the instruments of rule over the workers (merely as the instruments of the rule of capital itself) are mere consequences of the process of production; they are its products. Thus at the level of material production, of the life-process in the realm of the social - for that is what the process of production is - we find the same situation that we find in religion at the ideological level, namely the inversion of subject into object and vice versa. Viewed historically this inversion is the indispensable transition without which wealth as such, i.e. the relentless productive forces of social labour, which alone can form the material base of a free human society, could not possibly be created by force at the expense of the majority. This antagonistic stage cannot be avoided, any more than it is possible for man to avoid the stage in which his spiritual energies are given a religious definition as powers independent of himself. What we are confronted by here is the alienation [Entfremdung] of man from his own labour. To that extent the worker stands on a higher plane than the capitalist from the outset, since the latter has his roots in the process of alienation and finds absolute satisfaction in it whereas right from the start the worker is a victim who confronts it as a rebel and experiences it as a process of enslavement. At the same time the process of production is a real labour process and to the extent to which that is the case and the capitalist has a definite function to perform within it as supervisor and director, his activity acquires a specific, many-sided content. But the labour process itself is no more than the instrument of the valorization process, just as the use-value of the product is nothing but a repository of exchange-value. The self-valorization of capital - the creation of surplus-value - is therefore the determining, dominating and overriding purpose of the capitalist; it is the absolute motive and content of his activity. And in fact it is no more than the rationalized motive and aim of the hoarder - a highly impoverished and abstract content which makes it plain that the capitalist is just as enslaved by the relationships of capitalism as is his opposite pole, the worker, albeit in a quite different manner." ("Results of the Immediate Process of Production" 1863-1866 Marx, Appendix to Capital, vol. I, Penguin ed., pp. 989-90)
“the historic tendency of [capitalist] production is summed up thus: That it itself begets its own negation with the inexorability which governs the metamorphoses of nature; that it has itself created the elements of a new economic order, by giving the greatest impulse at once to the productive forces of social labour and to the integral development of every individual producer.” Letter from Marx to Editor of the Otyecestvenniye Zapisky 1877 <http://www.marxists.org/archive/marx/works/1877/11/russia.htm
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"Communism as the positive transcendence of private property as human self-estrangement, and therefore as the real appropriation of the human essence by and for man; communism therefore as the complete return of man to himself as a social (i.e., human) being – a return accomplished consciously and embracing the entire wealth of previous development. This communism, as fully developed naturalism, equals humanism, and as fully developed humanism equals naturalism; it is the genuine resolution of the conflict between man and nature and between man and man – the true resolution of the strife between existence and essence, between objectification and self-confirmation, between freedom and necessity, between the individual and the species. Communism is the riddle of history solved, and it knows itself to be this solution." <http://www.marxists.org/archive/marx/works/1844/manuscripts/comm.htm>
Ted