I believe that you are correct about the concept of existence, that it is not a real thing, but rather an artifact of our perception.
Which is why positivists say that something is only real if it can be perceived, directly or indirectly. They say that we only need to take into account things that can be perceived, because if it affects us, we are perceiving it.
Now that I think of this again, I see one possible flaw, if something is imperceptible now, it might still become perceptible later. For physical objects there might be a law to protect us, but our knowledge of non-physical (i.e. mental) objects leave much to be desired.
I believe that you are correct about the concept of existence, that it is not a real thing, but rather an artifact of our perception.
Which is why positivists say that something is only real if it can be perceived, directly or indirectly. They say that we only need to take into account things that can be perceived, because if it affects us, we are perceiving it.
Now that I think of this again, I see one possible flaw, if something is imperceptible now, it might still become perceptible later. For physical objects there might be a law to protect us, but our knowledge of non-physical (i.e. mental) objects leave much to be desired.