To F. C. Donders   20 April 1872

My dear Professor Donders.

Your kind letter is very encouraging. I feel sure that I have struck out nothing but what had better be omitted.¹ Few authors, I think, strike out half enough; & I am not half severe enough on my own writings. But I write now to say how generous your offer is about looking over my proof sheets.² I am however perplexed about accepting it. More or less physiology comes in in many parts, & I do not think it would be much good, unless I sent you all the sheets; & though the volume will not be a long one, this is greatly too much to expect from you. On account of the delay otherwise caused, it w^d be necessary to send to send you the first proofs, though I could run through them, just enough to see that they were intelligible. I always correct my proofs heavily, & it would be too great a loss to the publisher to make serious alterations in the second or corrected proofs. Therefore I have great scruples in accepting your very kind offer.

Moreover I doubt whether the book will have sufficient value to justify me in giving you this trouble. I had therefore better send only any sheets which at the same time seem to me the most doubtful. If you come to England in the summer we shall be delighted to see you here.³

Yours very truly obliged | Charles Darwin.