Although for most of our lives we have been told that everyone has their own taste and that we can like anything, maybe not everything you like is beautiful. If you believe that a specific art piece is beautiful, you could be mistaken. An art critique can think that it is simply horrific, and give you a bunch of reasons why. Which then would probably prove your opinion wrong.
Throughout time, we have been determined to find out what beauty really is and so far we have had no success at all. One could say that nature is beautiful, and many of us could possibly think of a building that we also like. The Louvre, for example, is a beautiful construction, but is it anyhow related to nature? No.
Can we know if something is beautiful? Or maybe, do we know what beauty is? The answer is no. Beauty is never known and it won´t ever. Beauty is the perception of an object to a specific individual. And however many people may agree that something is beautiful, it still doesn´t demonstrate that it is beautiful, because someone will not like it.