> "Death seems to be a harsh victory of the species over the particular
> individual and to contradict their unity. But the particular
> individual is only a particular species-being, and as such mortal. "
>
> http://www.marxists.org/archive/marx/works/1844/manuscripts/comm.htm
This isn't Marx endorsing any form of "altruism."
According to him, human being is potentially a "species-being" in the sense of a being able to develop the powers required to rationally self-determine willing and acting. Also according to him, rationally self-determined willing and acting are willing and acting in accordance with what Hegel called "universal existences, objects and aims," e.g. "the laws of beauty."
"Man is a species-being [20], not only because in practice and in theory he adopts the species (his own as well as those of other things) as his object, but – and this is only another way of expressing it – also because he treats himself as the actual, living species; because he treats himself as a universal and therefore a free being. ... An animal forms only in accordance with the standard and the need of the species to which it belongs, whilst man knows how to produce in accordance with the standard of every species, and knows how to apply everywhere the inherent standard to the object. Man therefore also forms objects in accordance with the laws of beauty." http://www.marxists.org/archive/marx/works/1844/manuscripts/labour.htm
This includes the universal ethical principles that constitute the ideal social relation as a relation of mutual recognition, an ethical claim explicitly made just before what you quote above.
"Activity and enjoyment, both in their content and in their mode of existence, are social: social activity and social enjoyment. The human aspect of nature exists only for social man; for only then does nature exist for him as a bond with man – as his existence for the other and the other’s existence for him – and as the life-element of human reality. ... Social activity and social enjoyment exist by no means only in the form of some directly communal activity and directly communal enjoyment, although communal activity and communal enjoyment – i.e., activity and enjoyment which are manifested and affirmed in actual direct association with other men – will occur wherever such a directexpression of sociability stems from the true character of the activity’s content and is appropriate to the nature of the enjoyment.
"But also when I am active scientifically, etc. – an activity which I can seldom perform in direct community with others – then my activity is social, because I perform it as a man. Not only is the material of my activity given to me as a social product (as is even the language in which the thinker is active): my own existence is social activity, and therefore that which I make of myself, I make of myself for society and with the consciousness of myself as a social being." http://www.marxists.org/archive/marx/works/1844/manuscripts/comm.htm
Ted