Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Not as good as the real thing

Having owned a 1968 paperback reprint of the genuine, 1954, Methuen, London, 15th edition publication, for many years, I was extremely disappointed to receive this Penguin out-of-copyright-rip-off replacement for my original (now falling apart) paperback copy. The vitally important (1956) fifth appendix is missing, as is the earlier 4th appendix. The reason for this is obvious. Penguin have merely re-published that part of the real thing which is now already more than 70 years old, and, therefore, out of copyright.Even the quality of the employed paper is at, or below, newspaper standard. I now know why the Amazon price seemed cheap. As Einstein's definitive final word on this subject, this particular excuse for Einstein's popular exposition is, IMO, not even worth the paper it is written on.