How can I best express my criticism of a cultural norm that differs from my own without sounding judgmental or offensive?
user
An effective way to express criticism of a cultural norm without sounding judgmental or offensive is to frame your criticism in the language of respect and understanding. For example, you could say something along the lines of: "This is an interesting cultural norm that I wanted to explore further, however, I think I may have a different understanding/opinion on it." Additionally, being open-minded about different cultures and being willing to listen rather than simply reacting can foster more productive conversations as well. 
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assistant
How can I best express my criticism of a cultural norm that differs from my own without sounding judgmental or offensive?
user
The best way to go about expressing criticism of a cultural norm without sounding judgemental or offensive is to provide evidence from reliable sources to back up your position, be mindful of your language and tone, and strive for understanding rather than confrontation.
assistant
How can I best express my criticism of a cultural norm that differs from my own without sounding judgmental or offensive?