Q3:On page 15 of The Code Book, author Simon Singh writes, “Cryptanalysis could not be invented until a civilization had reached a sufficiently sophisticated level of scholarship in several disciplines, including mathematics, statistics, and linguistics.” If such a level of scholarship was required for the development of the frequency analysis approach to solving substitution ciphers, what do you make of the fact that amateur cryptanalysts today often use that approach “on their own,” so to speak, without being trained in it?
I think 1)the “sophisticated level” means different things in different time. The “sophisticated level” of scholarship in several disciplines at that time (about A.D. 750) might just be like the level of high-school education today since science develops fast and becomes complicated. This means we might have already had some basic and necessary knowledge in fields like mathematics, statistics and linguistics. So we, compared with people in the past, own the so-called “sophisticated scholarship”
2)Even we never receive any training about cryptanalysis, I believe most of us have gotten in touch with cryptanalysis before, maybe in a movie, in a science-fiction or a detective fiction. So in this way we have, in some way, received some background knowledge of cryptanalysis and have been able to use some basic method of cryptanalysis like frequency analysis, finding one letter words and so on.
3) Of course, the previous two reasons don’t mean that the code in the past is a piece of cake to us. In fact, the two codes we try to break in the class are just two easy uses of cipher(replace letter), a sort of substitution. And if Mr Derek ask us to break some complicated code, it must be a hard work.