Final Principle: Fifteen-stories Stone Tower and the Great Plan
The stone tower with fifteen stories has existed since the construction of Komatsu Tenmangu in 1657 and it is believed that this tower is the oldest existing tower with fifteen stories in Japan, where, according to Nakanishi(1984), there existed no pagoda with more than thirteen stories in Japan. Since this tower does not have "sourin"（相輪）, a kind of symbol for pagoda, it was not intended as a pagoda tower.
In terms of comparative studies of various historic maps of Komatsu Castle along with contemporary maps, it is estimated that the castle's frontal water-flow (suikou, 水口）situated on the opposite side of the Kakehashi River along the stratight line FG. Furthermore, three points of B, F, and E are on a straight line and it is calculated that the ratio BF/FE is about 4/6, suggesting that point F corresponds to the rotation axis of a straight-beam balance with arms of unequal length.
4 9 2
3 5 7
8 1 6
Figure on the left shows the unique locational characteristics of the tower,
where point B indicates the center of the front line of "Haiden"
(the main worshipping hall), point E the center of the shrine gate, and
point F the center of the stone tower, where the stragiht line FG corresponds
to the line stretching from the true north to south direction.
Lo Shu is summarized in terms of nine numbers arranged as in figures on the left, where the sums of three numbers along the horizontal, vertical, and diagonal lines of the design of Lo Shu are all equal to the number fifteen. Based on this design, King Yu was able to complete the Great Plan, a kind of constitution to a ruler, aiding him in achieving the harmonious development of the nation or a feudal domain.
What does this mean? In order to answer this question, we have to summarize our knowledge: 1) Toshitune was acquatinted with Matunaga Sekigo whose representative writing titled "Irin-sho"advocated that a ruler such as feudal lord must cultivate both his own character and administarative skills to govern his domain; 2) The book title "Irin-sho"(彝倫抄）means to summarize the constant way man must always obey, and, the word "Irin" was first used in the section on the Great Plan (洪範）of the oldest Chinese history book titled Shang Shu (尚書） or Shu Jing （書経）. 3) From these historical facts, we may safely infer that both Matunaga Sekigo and Toshitune were well aware of what the Great Plan meant for a ruler. 4) The Great Plan with nine divisions was endowed to King Yu (禹）, founder of the Xia （夏）dynasty, who succeeded in controling the inundating waters, where Heaven gave Yu the Great Plan in terms of Lo Shu (洛書）that came out of the River Lo (洛水)..
Among nine divisions, it is judged that the 4th division（五紀）, the 6th division（三徳）, and the 5th division (皇極）are relevant here. .
Remembering that the fifteen-storied stone tower, sitated in front of the water source of Komatsu Castle, was constructed to animate strong mountain as the attribution of lord (Third Principle), we may safely conclude that the stone tower symbolizes the 5th division of the Great Plan. .
Sentences on the right explains nine divisions of the Great Plan, taken from 尚書 used in the shrine office in late Edo-period.
Copyright Komatsu Tenmangu 2007