My personal insight as led me to this claim. I'm not sure if there is any way to test it out, but I wish to share it: When you, for example, look at nature, then all the information of the trees, rivers, etc. is flowing through your brain. The moment you get a positive emotion from nature, then that naturalistic information in the brain gets combined with that positive emotional state. Thus, producing a positive emotion that literally contains a naturalistic quality to it. The same thing would apply if you got a positive emotion from looking at something artificial such as a lit flashlight. The positive emotion would take on the artificial tone of that flashlight. So, instead of seeing the flashlight and all its qualities, you are actually feeling all of its qualities. It would be no different than tasting a sweet piece of candy. You could either look at the piece of candy and all its sweet and delicious attributes, or you can taste them. In a way, I guess you could consider our positive emotions to be the taste we get from life itself. This means that, as I explain later on here, emotions are a sense like taste, sight, hearing, etc. Now, here's where things get interesting. I established earlier that our positive emotions are like the sense of taste. This means that if we have a good value judgment from nature or a lit flashlight that makes us feel a positive emotion from these stimuli, then we are sensing something good in our lives. Likewise, when we have a bad value judgment that makes us feel a negative emotion, then we are sensing something bad in our lives. Therefore, our positive emotions are a sense like sight and hearing. Without them, then we can see nothing good in our lives because it would be no different than a blind person. No value judgment this blind person makes can allow him to see just as how no value judgment of our lives having good value to us can allow us to see any good value without our positive emotions. The same thing applies to negative emotions. By the way, many people make a distinction between two types of emotions. The first type they would describe as the "lower emotions." These emotions are euphoric or dysphoric states. For example, a state of euphoria would be what I've described earlier as being a state induced by the brain's biochemicals such as a feeling of excitement or joy from the idea of getting a new movie, a feeling of love, or a generalized feeling of well being (i.e. calmness and relaxation). As for the 2nd type of emotions, these are the higher impulses. They would be something such as choosing to help someone in need when you don't have the 1st type of positive emotions at all. I personally think these 2nd type of emotions aren't anything at all. They do not allow us to perceive our lives as having any value to us. So, I will be referring solely to the 1st type of emotions when I discuss my whole theory to you in this topic.