129. The "Writing Brush" Radical: 聿
The "writing brush" radical 聿 is on duty in only one Joyo kanji, and it seems like the wrong one. I'm talking about this character:
粛 (1369: solemnly; silent; to tighten)
Though 聿 is tall and lovely, look how curtailed the radical is there, with its lower half deleted. As the definitions 粛 of reflect, this kanji has nothing to do with writing anymore.
By contrast, 書 (142: writing; book) does, but the Japanese file that kanji under radical 72, 日 ("sun"). And again the base of 聿 has disappeared.
Although a gorgeous, full expression of the 聿 shape appears in 建 (473: to build), the on-duty radical there is 廴, radical 54 ("long stride").
What Is the 聿 Radical Called?
The six-stroke 聿 radical looks just like this non-Joyo kanji:
聿 (brush; finally; self; relate; follow; here; fast)
But its イツ yomi does not carry over to the radical name. Instead, the Japanese call our radical ふで, which corresponds instead to the Joyo kun-yomi of this kanji:
筆 (569: brush; writing)
Here again we see a complete version of our radical, though 竹 (radical 118: "bamboo") is on duty.
When the 聿 radical lies on the right side of a kanji, the name ふでづくり applies. As "Radical Terms" explains, right-side radicals are called つくり (旁: side), with that term voiced in ふでづくり.
As for English names, "writing brush" works fine.
Photo Credit: Eve Kushner
In the name of the Kamakura temple 建長寺 (けんちょうじ), our radical stretches out fully in 建 (473: to build), as you can see on the signpost.
On the upper right, 臨済宗 (りんざいしゅう) denotes the pertinent Zen Buddhist sect or "school." The middle kanji in that term appears here with its old, non-Joyo shape 濟.
Kamakura has five important Rinzai temples, collectively called 鎌倉五山 (かまくらござん), and the 五山第一 (ござんだいいち) on the upper left indicates that 建長寺 is the first of those five (apparently being the most important). As to why 五山 (literally, "five mountains") stands for "five temples" here, Wikipedia explains that 山 represents "temple" or "monastery" in this context because many monasteries were built on isolated mountains.
Etymologies
I turned to Henshall's newer edition (the source of all etymologies in this Radical Note) to see why 粛 (1369: solemnly; silent; to tighten) contains a 聿 depicts a "hand holding writing brush." Strangely, he calls this shape the phonetic in 粛 but doesn't say what the radical would be. Perhaps he views the 聿 as serving both functions. He also mentions that one scholar takes this 聿 to represent "boat pole" and suggests that 粛 came to mean "be in awe" because one is careful when traveling by boat over deep water.
Although 粛 provides neither a satisfying 聿 shape nor a satisfying etymology involving a writing brush, the next etymology makes up for that:
筆 (569: brush; writing)
Henshall says that the simpler, older form of this character was simply 聿 (hand holding a writing brush). The ancient Chinese later added the "bamboo" radical, reflecting the typical bamboo shaft of a writing brush.
Though Henshall doesn't complete the thought, the addition of that "bamboo" radical split 筆 off from the non-Joyo 聿 (brush; finally; self; relate; follow; here; fast), making them different characters.
Here's what Henshall says about the other aforementioned kanji in which our radical is a mere component:
書 (142: writing; book)
An ancient form depicts a "hand holding a writing brush" over a reduced version of 者 (person). Henshall calls 者 the phonetic, which would likely make 聿 the on-duty radical, though he doesn't say. Because 者 phonetically conveys "imitate" or "write," the whole character represents "copy text, write."
建 (473: to build)
Henshall calls this 聿 "writing brush held upright" and says that the current left-side radical appeared in error. In an older form a different left-side radical meant "move slowly" or "go, move forward," so the entire character represented "move writing brush." Because one holds a brush upright when writing, 建 came to mean "hold/stand timber (etc.) upright/erect," which later extended to "build."