Logically you're right but it looks like you may be overthinking this one

"Takes one to know one" is a set expression more or less meaning people who live in glass houses shouldn't throw stones

Also, it doesn't ALWAYS take one to know one. That's why I can call Joe Biden a child rapist and retarded traitor, and my mother a good woman, and Wayne Gretzky the best hockey player ever, while being none of those myself.

Logically you're right but it looks like you may be overthinking this one

"Takes one to know one" is a set expression more or less meaning people who live in glass houses shouldn't throw stones

Also, it doesn't ALWAYS take one to know one. That's why I can call Joe Biden a child rapist, and my mother a good woman, and Wayne Gretzky the best hockey player ever, while being none of those myself.

Logically you're right but it looks like you're overthinking this one

"Takes one to know one" is a set expression more or less meaning people who live in glass houses shouldn't throw stones

Also, it doesn't ALWAYS take one to know one. That's why I can call Joe Biden a child rapist, and my mother a good woman, and Wayne Gretzky the best hockey player ever, while being none of those myself.