on principle

Idioms  

1. On moral or ethical grounds. As James Russell Lowell wrote about Alexander Pope in 1871, “There was a time when I could not read Pope, but disliked him on principle.” [First half of 1800s]

2. According to a fixed rule or practice. For example, The police were locking up the demonstrators on principle . [First half of 1800s]

3. on general principle . For no special reason, in general, as in Dean won't touch broccoli on general principle . [First half of 1800s]

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Example Sentences

Touma-Suleiman opposes the death penalty on principle and argues the bill also goes against international law and past treaties signed by Israel.

From BBC • Jan. 31, 2026

Warsh didn’t spend years positioning himself for this job to torch it on principle.

From MarketWatch • Jan. 30, 2026

While rejecting discriminatory pricing on principle, they are also worried for practical reasons, as staff will now need to check visitors' identity papers.

From Barron's • Jan. 13, 2026

Mr. McConnell has been a consistent, thoughtful supporter of presidential powers, and he continued to stand on principle on Thursday.

From The Wall Street Journal • Jan. 9, 2026

Koffi tensed on principle at the sight of him.

From "Beasts of Prey" by Ayana Gray