I guess we are just a tick on the eternal "timeline"....defined by humans...we only know what we can "humanly" comprehend.....and to ask what do I know assumes an ultimate truth to know? Or are we just what we have observed and cataloged in our mental storage? But perhaps more importantly....why do we think it matters? Is it we are more than matter? And while its fun to get "existential" unfortunately I need to get back to my physical reality....