deceptive perception?

Perhaps our problem is faulty perception? I glanced up from the computer screen to idly consider what a moment of arrival would be like for a civilisation such as ours, which is occupied with progress, only for my eyes to focus involuntarily on an object in the middle-distance across on the other side of the street. So now there is a displacement in inverted colours: a light-shadow superimposed up and to the right-hand side onto what I now see: the formerly unseen object. Here is an impression of a green glowing chimney beneath a cloudy sky. I am simultaneously seeing the object and my memory of it. And the memory is rapidly fading. As a memory and representation of a thought, this could be a fading presence of a civilisation.