False Blocks NR example

[eaborch2]

Hi,

I was looking over page 81, specifically false blocks. With the example given, shouldn't the conditional statement on the bottom be R N? With it set up as R [N R], it is impossible for two or more new compositions to appear in a row as suggested in the last sentence of the page, and I feel that it negates what the paragraph above the conditional diagram was stating. Am I just reading this wrong or is there an error?

[Nikki Siclunov]

Hi eaborch2,

Thanks for your question. The rule in question states, "each rock classic is immediately preceded by a new composition." In other words, IF the song is a rock classic (R), THEN there must be a new composition immediately before it (NR):

R NR

The rock classic is a sufficient condition; the new composition preceding it is the necessary condition. We cannot have two rock classics in a row, because every time we have R we need to have N immediately preceding it (hence, the RR Not-Block). The rule clearly allows, however, for two or more new compositions to appear in a row: the NR block is only a necessary condition for R, not an absolute mandate that must occur no matter what. If, say, the third song were a new composition, a NR block would unnecessary. In fact, absent some other rule(s) to the contrary, this rule alone would allow for all seven songs to be new compositions.

Does that make sense? Let me know.

Thanks!