(Mi wo sutete koso ukabu se mo are;
“There are rivers that you cross by throwing away your body”)
Sometimes facing danger head-on is the only way to escape it. There are times when you need to be willing to take a risk in order to deal with a situation. Similar to “nothing ventured, nothing gained,” but the goal is often survival or avoiding some bad result rather than pure profit. A drowning person’s struggles may only make their situation worse; the image is of floating to the surface and escaping by relaxing and entrusting one’s body to the water instead of by fighting it.
We begin with the noun 身 (mi), “body,” marked as the object of a verb by the particle を (wo). The verb is 捨つ (sutsu), “to throw away,” in conjunctive form, with the perfective suffix つ (tsu), also in conjunctive form. This verb phrase is in turn followed by emphatic particle こそ (koso). The following clause begins with the verb 浮かぶ (ukabu), “to float,” in prenominal form, attached to and modifying the noun 瀬 (se), often used to refer to the “shallows” of a river (the part where you ford it), but in this case possibly referring to the “rapids.” In either case, se is marked by the particle も (mo), here serving to emphasis that “this kind of river-part does also exist.” And finally we get the verb あり (ari), “to be,” in perfective form.
Why is the final verb in perfective form instead of sentence-final form? Well, it turns out that in classical grammar, this was just kind of how you did it following koso, in effect using an unusual form at the end of the sentence to remind the reader/listener of the emphasis and focus from earlier.
If you watch enough semi-realistic anime fights, you’ll probably notice this trope in action: rushing into the opponent’s space without hesitating is a dangerous move, but when used properly it can give an advantage or at least lessen the strength of the opponent’s attack where holding back (i.e. failing to “throw away the body”) would have resulted in being struck down.
There’s another saying that references fords, 立つ瀬がない (tatsu se ga nai), meaning that someone has lost face or is in a troublesome situation. Naturally, mixing these up and saying 身を捨ててこそ立つ瀬もあれ is an error.
This saying is descended from a 1632 kanazoushi called 尤双紙 (Mottomo no soushi).
(“Karate wa mi wo mamoru tame no undou da to itte mo, uchiwaza wo ukeru kokorogamae ga nakereba benkyou ni naran. Tsumari, mi wo sutete koso ukabu se mo are to iu koto da.”)
[“You can call karate a kind of exercise that protects your body, but if you’re not prepared to take a blow then you won’t be able to learn. In other words, it’s only by passing through danger that you reach safety.”]