A section of a long and splendid literature can be most conveniently treated in one of two ways. It can be divided as one cuts a currant cake or a Gruyere cheese, taking the currants (or the holes) as they come. Or it can be divided as one cuts wood - along the grain: if one thinks that there is a grain. But the two are never the same: the names never come in the same order in actual time as they come in any serious study of a spirit or a tendency.