てしかるべきだ

The expression てしかるべきだ is a formal and literary way of saying "should," "ought to," or "it is only natural/appropriate that." It conveys a strong sense that something is the proper, expected, or reasonable course of action. The phrase derives from the classical Japanese verb しかる然る (しかる, "to be so/thus") combined with べき ("should"), literally meaning "it should be so that…"

This grammar point is used primarily in written language, formal speeches, editorials, and academic or bureaucratic contexts. It carries a tone of moral judgment or logical necessity – the speaker believes the action is what ought to be done as a matter of course.

Formation

Attach しかるべきだ to the て-form of a verb:

Nuance

Compared to more common expressions like 〜～べきだ or 〜～はずだ, てしかるべきだ is considerably more formal and emphatic. It implies that the speaker sees the action as not merely advisable but as something that is rightfully expected or only natural. It often carries a critical tone, suggesting that the current situation falls short of what is appropriate.

しかるべき as a modifier

The form しかるべき (without だ) is also common as a noun modifier meaning "proper," "appropriate," or "due":

This adnominal usage is very common in business and official communication.