…than to be shot down.
(Reiri naru atama ni wa tojitaru kuchi ari;
“In the clever head, a closed mouth.”)
A wise person doesn’t speak any more than necessary, and thus doesn’t say foolish, boring, or pointless things. “Silence at the proper season is wisdom.”
We begin this complete sentence with the compound noun 怜悧 (reiri), “cleverness,” “wisdom.” This is followed by the copular particle なり (nari) in prenominal form as なる, allowing it to attach to and modify the noun 頭 (atama), “head.” Next we get the locational particle に (ni), doubled up with the topic marker particle は (wa); that is to say, the topic of this phrase is “as for in-the-head-that-is-wise.”
The comment on this topic centers on the noun 口 (kuchi), “mouth.” It is preceded by the intransitive verb 閉づ (todzu), “to close,” in conjunctive form and taking the auxiliary verb たり (tari), which indicates that the verb it modifies is in a conclusive or continuative state; also in prenominal form so that it may prefix the noun. And following kuchi is the copular verb あり (“to be”), in conclusive form.
This obscure saying is attributed to an admiral of the Imperial Japanese Navy, Yamamoto Isoroku; perhaps it’s appropriate then that he died thanks to a broken code allowing his plane to be targeted by the US Air Force.
(“Gakusei jidai wa shakai fuan no sei de amari kuchi wo kikanakatta ga, sono sei de reiri naru atama ni wa tojitaru kuchi ari de hikaeteiru no da to omowarete, kurasumeito ni wa kakkou ii to bunfusouou na shousan wo uketeita.”)
[“When I was a student I almost never spoke out of social anxiety. But people thought that I was holding back because of how the wise speak only when necessary, and my classmates showered me with undeserved praise about how cool I was.”]