i saw, i was, i know

i saw the pyramids
i saw them fall
i was there at the beginning of it all

i was there in secret
i was there in descise
i was there to bring hope to their eyes

and seeing it all made me think
and knowing it all made me think some more
no one could see me for i was right infront of their eyes

people always took me for granted
until i was gone
then they cursed me for not being there
when they needed me most

so can you guess who or what i am yet?
if you cant i dont blame you
because even i dont know