First published in 1930 in the journal Proletarskaya Revolyutsiya No. 1.
Sent from Paris to Moscow.
Source: Lenin Collected Works, Progress Publishers, 1977, Moscow, Volume 37, pages 422-423.
Translated: The Late George H. Hanna
Transcription\Markup: D. Moros
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April 5, 1909
Yesterday I received the made-up pages of signatures 14–20 (pp. 209–320) which I already have (the only page proofs I have not now received is signature 10, i.e., pp. 177- 192) and today I got galleys 226–234 (pp. 784–809 of the MS).
I am sending the misprints in signature 14 (pp. 209–224) —the misprints in the other signatures have already been sent—and corrections to the galleys. Actually there is one important correction here; in galley 234 (end of the first paragraph in Section 7 “on a Russian ’idealist physicist”’) —page 809 of the manuscript—the words “materialist and thinker, Professor V. I. Vernadsky” have been set. This completely distorts the meaning. It should read “natural scientist and thinker”, etc.
If it is too late to correct it, there absolutely must be a notice of this misprint on a separate sheet since it distorts the meaning.
In answer to your question “where to put pages 802a and 802b and where are they? They are not in the manuscript”—those pages were sent separately (from Geneva) and they must be placed as a footnote to the word “object” on line 7 in the paragraph (in Section 6) that begins with the words “Rey became muddled because” (this is galley 232 and page 802 of the manuscript).
In any case (i.e., in case these specially sent addenda did not reach you) I am sending them again. You must not, of course, delay the book on account of them. It seems that the book is “delaying itself” sickeningly at the publisher’s ... ad infinitum. Obviously it will not come out before Easter!...
Very best regards. I send Mother kisses and hope you will both soon be in the Crimea.
 The footnote was included (Collected Works, Vol. 14, p. 297). —Ed.
 I have a copy of that addendum (footnote to p. 802) written on a single page with another addendum (end of Section 7, p. 812 of the MS). They have probably both been lost and I am repeating them both. The printing of the book must not be delayed for either of them.—Lenin
 There follows, in the original, a list of the misprints.—Ed.
 This misprint was not given in the list of errata nor was it corrected in the text of the first edition of Materialism and Empiriocriticism. It was first corrected in the Third Edition (Russian) of, the Collected Works (see Collected Works, Vol. 14, p. 300).