This proposition, which, in my opinion, is destined to do for history what Darwin's theory has done for biology, we, both of us, had been gradually approaching for some years before 1845. How far I had independently progressed toward it, is best shown by my "Condition of the Working Class in England."(b) But when I again met Marx at Brussels in the spring of 1845, he had it ready worked out, and put it before me, in terms almost as clear as those in which I have stated it here. From our joint preface to the German edition of 1872, I quote the following: "However much the state of things may have altered during the last twenty-five years, the general principles laid down in this Manifesto are, on the whole, as correct to-day as ever. Here and there some detail might be improved. The practical application of the principles will depend, as the Manifesto itself states, everywhere and at all times, on the historical conditions for the time being existing, and for that reason no special stress is laid on the revolutionary measures proposed at the end of Section II. That passage would, in many respects, be very differently worded to-day. In view of the gigantic strides of modern industry since 1848, and of the accompanying improved and extended organization of the working class; in view of the practical experience gained, first in the February revolution, and then, still more, in the Paris Commune, where the proletariat for the first time held political power for two whole months, this programme has in some details become antiquated. One thing especially was proved by the Commune, viz., that 'the working class cannot simply lay hold of the ready-made State machinery, and wield it for its own purposes.' (See 'The Civil War in France; Address of the General Council of the International Workingmen's Association,' London, Truelove, 1871, p. 15, where this point is further developed.) Further, it is self-evident that the criticism of Socialist literature is deficient in relation to the present time, because it comes down only to 1847; also, that the remarks on the relation of the Communists to the various opposition parties (Section IV.), although in principle still correct, yet in practice are antiquated, because the political situation has been entirely changed, and the progress of history has swept from off the earth the greater portion of the political parties there enumerated. "But, then, the Manifesto has become a historical document which we have no longer any right to alter." The present translation is by Mr. Samuel Moore, the translator of the greater portion of Marx's "Capital." We have revised it and I have added a few notes explanatory of historical allusions. FREDERICK ENGELS. London, January 30, 1888.