Hi there,

One day, I heard my colleague talk with our boss. The first sentence of his was: 'Mr. Owen, I want to talk to you'. But I think he should have said, ' I want to talk with you.' It is because 'talking to someone' may sound that the speaker is superior to the listener. (Is it true?) Do you think 'talking with you' is more appropriate in the above case? Is there any difference between 'speak with someone' and 'speak to someone'?

No, it's actually "speak to you" that implies superiority. There's a dreaded phrase that teachers use: "I want to speak to you after class." The student invariably recoils in panic, and spends the rest of the class period speculating on why the teacher wants to speak to him. In my opionion, "Mr. Owen, I want to talk to you." (notice "talk" not "speak"), actually sounds friendly and pleasant in my opionion. Notice he didn't say: "Mr. Owen, can I speak to you for a moment?" Mr. Owen would have probably said that to him though. What's interesting is that he said "Mister" Owen, rather than call him by his first name. Over here, the titles "Mister" and "Missus" and "Miss" are quickly being retired, and most people use first names only even in the most formal business settings.
There is a slight difference in meaning between the two sentences.

"I want to talk to you," implies that the speaker is going to tell Mr.Owen something and that the exchange may be one sided. He is speaking to Mr. Owen. Mr. Owen may or may not say anything back, but it is not necessary for him to do so.

"I want to talk with you" implies that a conversation will be going on with both the speaker and Mr. Owen contributing to it. Mr. Owen has to participate and contribute or else someone is talking "to" him. and not "with" him.

Basically, the difference is who is going to be doing most of the talking. If your colleague is planning on making a business proposal or a complaint while Mr. Owen sits and listens then "to" is appropriate since he is doing most of the talking. If your colleague is planning on having a discussion or a friendly chat with Mr. Owen with a lot of back and forth then "with" is appropriate since both people are speaking an equal amount.
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It's sooooooooo interesting!

to talk and to speak have the same meaning regarding the prepositions "to" and "with"!
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