The Grammarphobia Blog

Giving diligence its due

Q: Your recent entry on “due process” made me think of “due diligence,” as in “He did due diligence,” which is an odd one to parse. If “diligence” means “conscientiousness,” then it’s not really something one does, is it? Just a thought for a rainy day when you don’t have a blog idea … although the supply seems inexhaustible.

A: Well, it’s a rainy day, but the supply is indeed inexhaustible. In fact, I apologize to all those who’ve sent in questions but haven’t gotten answers yet.

Now, let’s give diligence its due.

In the phrase “due process,” first recorded in 1447 (more fully, “due process of law”), the adjective “due” means proper or in accordance with established rules, according to the Oxford English Dictionary.

As for “due diligence,” first recorded in 1598, “due” means appropriate, sufficient, or proper. This sense of the adjective has been in use since around 1400.

The word “diligence” here carries more of an active than a passive sense. It means care and attention, industry, endeavor, and effort to accomplish what is undertaken.

So “due diligence” means something like “the necessary care” or “the effort required.” And one can “exercise” or “perform” or “do” it.

Now, I’d better get back to exercising due diligence on the rest of the questions in my mailbox.

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