I have found that I can substitute the word "AND" instead of "BUT" in most any conversation.   Often I want to disagree before agreeing to what someone else is saying.  Thats OK - but its not conducive to listening much less validating a persons thoughts.    In sales we seek to listen and ask questions first.    I have found that I say I am a good listener - but often my analytical side kicks in and I have to interject my own thoughts instead of validating what the other person is saying.

There are a bunch of variations to the "But" response - and almost all of them are condescending and dismissive.  One expression I use after my wife suggests something I dont agree with is "That may be so...."    And sometimes I say "Thats a good idea, but what about...."    And in many of my deep conversations with long time analytical friends - I might say abruptly - "I dont agree" or even "You are completely wrong - and let me tell you why"

None of this kind of conversation is great for establishing new relationships - much less cultivating existing ones.  Conversations are best when they are amplifying not dialectic. 

I know it pains us to agree with what someone else is saying - particularly when you have a strong opposing idea.  But one solution to this is to amplify what the person is saying by contributing to their thought by responding with "And this other thing could be considered".    So the next time you feel compelled to respond with "Yes, But..." - try saying "And ..."

A corollary to using AND instead of BUT to develop the conversation is to not feel like you have to respond - and instead ask an amplifying question.  If someone says something you don't agree with or don't completely understand - try just asking some questions.  You might learn something and make a connection at the same time.