This is a bit from the Sumibiki (Crossed-out) chapter of the Nampouroku (The Southern Record) on my favourite subject: kanewari!^_^

1. What are kanewari?
From the Shoin-style daisu to Soan-style tea, the number of kanewari has already been decided. Since nobody knows how it was decided which ruler to originally rely upon, it is quite a bother.
There is an approximate measure based on the order of heaven and earth. Adding doyo to the four seasons makes five. Adding the center to the four directions makes five. The day is divided into five from the hour of the dragon to the hour of the monkey. The night is divided into five hours. Yin and yang are each explained by five elements. A person, too, is divided into five body parts. Thus we have a ruler for establishing five kane from things such as these. There is no difference between large and small kane. There are five yang kane. Yang is what expresses the shape (katachi). The space between these five kane are six yin kane. Formally, we use the five yang kane. We don’t usually use the six kane. In Soan-style chanoyu, there are circumstances under which the yin and yang are used together, which is said to be based upon the formal daisu and formal shoin-style tea. This is based on the circumstances under which both yin and yang are used together with the shoin-style daisu. If one doesn’t understand what circumstances, mistakes will occur without a doubt. If one investigates the foundations of kane intimatly, one can use them freely however one likes, it is said.