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

Nor are they on principle opposed to immigrants.

From The Wall Street Journal

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

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

From MarketWatch

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

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