This is a perplexing yet fascinating conjecture: Suppose there is such a thing, it exists somewhere tangibly, yet neither you nor anyone you know has ever heard of any information related to this thing. You don't know its appearance, don't know its origin, don't know its location, and don't even know if it exists. No one has ever told you that such a thing exists somewhere in the world. At the same time, this thing will not affect you in any way, whether it be its birth, evolution, or extinction, it will not intersect with your information in any way.
So, does it truly exist for you?
When this thing disappears for some reason, does this event truly occur for you?