When you classify things as positive and negative, you get stuck with both simultaneously, as one cannot exist without the other. Remember that for every action there is an equal and opposite reaction: this is a law established by Newton, but Newton did not create it. Nature did. Because nature strives for neutrality and that momentum is driven by an underlying state of non-duality (which, sadly, we can hardly experience because our thinking is limited, be it positive or negative).
So if everything is underlying neutral, and positive and negative are just a matter of perception, does that mean we must live to completely eliminate positive and negative thoughts? Should we try to “dull” our perception so that we can experience everything as it really is, that is, as a continuous, amorphous and totally connected nothing? And wouldn’t that put us at risk of becoming a kind of vegetable, never feeling much of anything (low or high), existing in a uniform and unemotional state? Is that a goal worthy of our time and our life?
Not to worry! Humans can’t even come close to this (unless we’re experiencing some serious brain damage, which I definitely don’t recommend). For whatever reason, we think what we think (perceived as “positive” or “negative”) before we can think about it, that is, thoughts are much faster than we are and out of our control. They come and go all the time, despite us.
So in this human body we will continue to record thoughts, and it’s not about controlling the thought itself (you can’t do that), it’s about the weight you assign to that thought as an observer (which you can control, if you’re skilled enough) . A thought comes along, maybe it seems positive, or maybe it seems negative. A corresponding feeling is generated. Don’t give it any importance. Don’t judge it, it will go as fast as it came (it always does). And a next state will come (before you know it and, of course, completely out of your control). Do the same with the following thought and the feeling it generated. Did it make you mad? Don’t judge it! Just experience the anger, which of course will go away as quickly as it came (unless you care about it). Or maybe the thought made you happy. Don’t praise it! Just experience happiness, but don’t get too attached because this too will pass.
As you can see, it is not about what you are thinking, but about the judgments you have about what you are thinking. In other words, pay attention to the attitude with which you are observing your thoughts and the emotional states that they generate. Don’t try to think positive because the more you do it, the more negativity you’ll bring out to balance things out. Instead, think smartly, accepting and experiencing life’s seeming richness (happy, sad, low, or high) without taking anything too seriously. After all, life is just a game. Play smart and you will win.