(There’s a spelling-only pun in here that I didn’t notice until the post was almost entirely written; bear in mind that the Land of Nu sides with those who stand against fascism.)
(Jison no tame ni biden wo kawazu;
“For the sake of your descendants, do not buy good fields.”)
If you leave your children a large and fruitful inheritance, then they don’t need to work for their living and tend to end up leading heedless lives without needing to actually learn about the world or the value of real work. This ultimately harms them, so it’s actually best for your family to avoid building up and leaving behind a fortune.
We begin with the noun 児孫 (jison), literally “children and grandchildren,” more figuratively “descendants.” The associative particle の (no) connects this to the noun ため (tame), “benefit,” “sake.” This combines with directional particle に (ni) to create the set phrase ～のために (~no tame ni), “for the sake of ~” or “to the benefit of ~.”
The thing you do for the sake of your descendants is an independent clause that begins with the noun 美田 (biden, which sounds like “bee then”), literally “beautiful field,” more figuratively “fertile field.” The particle を marks this as the direct object of the verb 買う (kau), “to buy,” which appears in imperfective form and takes the negative suffix ず (zu), which appears in conclusive form.
A more common term for “descendants” would be 子孫 (shison), but that is not used in this saying.
This phrase comes to us from a poem sent by Saigō Takamori, a samurai who was instrumental in the Meiji Restoration, to Ōkubo Toshimichi, one of his peers. It may be notable that while benefiting from a hereditary title and position himself, he cooperated with the widespread social reforms that the new imperial government implemented in the early days of the Meiji era.
(“Zaisan no kubukurin wo jizen katsudou ni tsuiyashitai to itteiru Biru Geitsu fuufu wa jison no tame ni biden wo kawanu tsumori kamoshirenai ga, jibun no kodomo-tachi ni sorezore issenman doru zutsu nokosu yotei rashii.”)
[“In saying that they want to spend 99% of their wealth on charity, Bill and Melinda Gates likely believe that they’re helping their descendants by not leaving a fortune, but supposedly they still plan to leave each of their children ten million dollars.”]