Why "silent rules"? Poetry is made of sound, in the form of speech, but is governed by rules which are not stated explicitly. As a help to readers, we try to tease out and make plain these silent rules. You have to perceive the structure of a work in order to read it. The subtitle is "inside and out" and becoming an insider involves knowing what the silent rules are. So much of the staging of modern poetry has operated a kind of "stereo blindness", in which whatever is visible to observer A is invisible to observer B, and vice versa. Annulling territoriality and blocks on visibility, we try to disengage a "cultural field", a low-resolution set of gradients which on mapping displays the cultural space inside which every literary move takes place. If you populate all the squares, eventually you have the map. By setting things in their true relations, much that had been suppressed or denied emerges in the light of day. The "hero of the piece" is the entire landscape, the awe-inspiring span from one end of the poetry world to the other. This completes the "heptagonal vortex", a set of seven volumes about British poetry in the period 1960 to 1997. The message is that poetic merit is scattered over the landscape and that loyalty to a faction is not compatible with full aesthetic principles and a thorough approach to collecting primary evidence.