To sum up the position of these articles, infliction of proportionate physical pain by lawful public authority as a punishment for a crime already committed is not intrinsically evil, but excluding it is likely a practical consequence in current circumstances. On the other hand, inflicting physical pain by one without authority or to frighten opponents or satisfy hatred, or to coerce the will or extract confessions (what the word “torture” generally entails), are unjust.
Personally, I don’t see why relatively quick physical pain is worse than psychological or other negatives being applied. Here’s an interesting article on this (the author’s original article he links to is good too).
If you’re talking about parents (who have authority over their children), there’s nothing per se wrong with a parent inflicting proportionate pain (key word being proportionate–for a child that is not going to be much and it will be quick, otherwise it becomes abuse) as part of disciplining a child, but other methods may be more advisable for a variety of reasons.
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