Zwicky was right for the wrong reason.
Could you please rephrase the sentence basing on the context for me?
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I can't give you the technical reasons detailed in the video on why Zwicky was wrong, but I can give you an example of "right for the wrong reason":
I believe that the planet Venus is hotter than earth because it is closer to the sun. However, Venus is hotter than earth not because it is closer to the sun, but because of its extremely thick atmosphere that traps heat. So, yes, I am right that Venus is hotter than earth, but the logic and evidence that I provided to support my claim was wrong. I was right for the wrong reason.
To be right for a reason. = idiom.
Grammar: You write or say something that is grammatically correct or right. Not because you know it but because you are lucky.
In that case, you would be right for the wrong reason: luck, not knowledge.