We don’t want to know what people are thinking. If you had the ability to hear people’s thoughts, you would want to shut it off after about 5–10 minutes.
People think thousands of thoughts per day and it never really stops. Imagine what it would be like to hear them constantly rattling on? And not only that, but you would be hearing the thoughts of everyone around you, not just one person. I think I would go a little nutty in that instance.
Also, thoughts are very private. Would you want someone else listening to all your thoughts 24/7?
If you are trying to figure out what someone is thinking about a specific situation, etc. then why not just ask them how they feel or what they think?
Most people will surprise you in their answers and most are willing to share if asked.