Well, Art is Art, isn't it? Still, on the other hand, water is water. And east is east and west is west and if you take cranberries and stew them like applesauce they taste much more like prunes than rhubarb does. Now you tell me what you know.

This quote is saying that art is unique, and can’t be compared to anything else. It’s emphasizing the idea that things are what they are, and can’t be changed. It then provides an example of this, mentioning the difference between east and west, and how cranberries have their own unique taste. It then suggests that to truly understand this concept, we should think about it and consider what we know.