Wage-labour is alienating.
What constitutes the alienation of labour?
Firstly, the fact that labour is
external to the worker – i.e., does not belong to his essential being; that he, therefore, does not confirm himself in his work, but denies himself, feels miserable and not happy, does not develop free mental and physical energy, but mortifies his flesh and ruins his mind. Hence, the worker feels himself only when he is not working; when he is working, he does not feel himself. He is at home when he is not working, and not at home when he is working. His labour is, therefore, not voluntary but forced, it is
forced labour. It is, therefore, not the satisfaction of a need but a mere
means to satisfy needs outside itself. Its alien character is clearly demonstrated by the fact that as soon as no physical or other compulsion exists, it is shunned like the plague. External labour, labour in which man alienates himself, is a labour of self-sacrifice, of mortification. Finally, the external character of labour for the worker is demonstrated by the fact that it belongs not to him but to another, and that in it he belongs not to himself but to another. Just as in religion the spontaneous activity of the human imagination, the human brain, and the human heart, detaches itself from the individual and reappears as the alien activity of a god or of a devil, so the activity of the worker is not his own spontaneous activity. It belongs to another, it is a loss of his self.
The result is that man (the worker) feels that he is acting freely only in his animal functions – eating, drinking, and procreating, or at most in his dwelling and adornment – while in his human functions, he is nothing more than animal.
It is true that eating, drinking, and procreating, etc., are also genuine human functions. However, when abstracted from other aspects of human activity, and turned into final and exclusive ends, they are animal.
We have considered the act of estrangement of practical human activity, of labour, from two aspects:
(1) the relationship of the worker to the product of labour as an alien object that has power over him. The relationship is, at the same time, the relationship to the sensuous external world, to natural objects, as an alien world confronting him, in hostile opposition.
(2) The relationship of labour to the
act of production within labour. This relationship is the relationship of the worker to his own activity as something which is alien and does not belong to him, activity as passivity, power as impotence, procreation as emasculation, the worker’s own physical and mental energy, his personal life – for what is life but activity? – as an activity directed against himself, which is independent of him and does not belong to him. Self-estrangement, as compared with the estrangement of the object mentioned above.
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In the same way as estranged labour reduces spontaneous and free activity to a means, it makes man’s species-life a means of his physical existence.
Consciousness, which man has from his species, is transformed through estrangement so that species-life becomes a means for him.
(3) Estranged labour, therefore, turns man’s species-being – both nature and his intellectual species-power – into a being alien to him and a means of his individual existence. It estranges man from his own body, from nature as it exists outside him, from his spiritual essence, his human existence.
(4) An immediate consequence of man’s estrangement from the product of his labour, his life activity, his species-being, is the estrangement of man from man. When man confront himself, he also confronts other men. What is true of man’s relationship to his labour, to the product of his labour, and to himself, is also true of his relationship to other men, and to the labour and the object of the labour of other men. - Marx,
Economic and Philosophical Manuscripts of 1844
When the alienating nature of labour is cast off, labour will no longer be a coerced activity of degradation and slavery. Then and only then does labour then become "life's prime want", that is, a positive expression of man's "species being" (or human nature if you will).