“In capitalist society spare time is acquired for one class by converting the whole life-time of the masses into labour-time.”

Collected Works, Vol. 10, pp. 83–87.
Collected Works

The Abolition of Work (1985)
Context: I am not playing definitional games with anybody. When I say I want to abolish work, I mean just what I say, but I want to say what I mean by defining my terms in non-idiosyncratic ways. My minimun definition of work is forced labor, that is, compulsory production. Both elements are essential. Work is production enforced by economic or political means, by the carrot or the stick. (The carrot is just the stick by other means.) But not all creation is work. Work is never done for its own sake, it's done on account of some product or output that the worker (or, more often, somebody else) gets out of it. This is what work necessarily is. To define it is to despise it. But work is usually even worse than its definition decrees. The dynamic of domination intrinsic to work tends over time toward elaboration. In advanced work-riddled societies, including all industrial societies whether capitalist or "communist," work invariably acquires other attributes which accentuate its obnoxiousness.
Usually—and this is even more true in "communist" than capitalist countries, where the state is almost the only employer and everyone is an employee — work is employment, i. e., wage-labor, which means selling yourself on the installment plan. Thus 95% of Americans who work, work for somebody (or something) else. In the USSR or Cuba or Yugoslavia or Nicaragua or any other alternative model which might be adduced, the corresponding figure approaches 100%. Only the embattled Third World peasant bastions — Mexico, India, Brazil, Turkey — temporarily shelter significant concentrations of agriculturists who perpetuate the traditional arrangement of most laborers in the last several millennia, the payment of taxes (ransom) to the state or rent to parasitic landlords in return for being otherwise left alone. Even this raw deal is beginning to look good. All industrial (and office) workers are employees and under the sort of surveillance which ensures servility.

Introduction and Plan of the Work, p. 2.
(1776)

1820s
Source: Speech to the House of Commons on Parliamentary reform, 25 April 1822

The Irish Worker, 29 August, 1915. Reprinted in P. Beresford Ellis (ed.), James Connolly - Selected Writings, p. 248

Collected Works, Vol. 5, pp. 25–30.
Collected Works

"Concerning the production of Consciousness"
The German Ideology (1845/46)

Without these it could not be. Socialism and ethics are two separate things. This fact must be kept in mind. Whoever conceives of socialism in the sense of a sentimental philanthropic striving after human equality, with no idea of the existence of capitalist society, is no socialist in the sense of the class struggle, without which modern socialism is unthinkable. Whoever has come to a full consciousness of the nature of capitalist society and the foundation of modern socialism, knows also that a socialist movement that leaves the basis of the class struggle may be anything else, but it is not socialism.
No Compromise – No Political Trading (1899)