謀はかりごとは密みつなるを良よしとす

expression, suru verb (precursor)

strategies must be kept secret to succeed

A classical proverb emphasizing that plans and strategies are best kept confidential; secrecy is essential for success. The phrasing uses classical grammar (なる attributive form of なり, and す as precursor to modern する).

• 「謀はかりごとは密みつなるを良よしとす」という言こと葉ばがあるように、作さく戦せんは秘ひ密みつにしておくべきだ。

  As the saying goes, 'strategies cannot succeed unless they are kept secret,' so you should keep your plans confidential.