Creation and the new covenant...

I am genuinely puzzled as to how someone can walk around God's
beautiful creation and not see His hand in it. It screams His name
everywhere. A leaf, has veins to provide water up from the ground,
breathes what we breathe out (to help cycle air), and has little
receptors that make it beautiful and green. I don't have a clue how or
why a flower comes out off of some trees and bushes. I dont understand
all the inner workings of the cell that makes it up. But someone who
truly does understand? How can they not just stand in wonder at God's
creation?

I know how complicated a watch's inner workings are, if I take one
apart. I cannot possibly believe that if you drop all of the pieces on
a table enough times that the watch will someday be put together. In
effect this is what a world without a creator is. But then you have to
imagine that the watch pieces aren't there to begin with. Nothing is
dropped. And nothing is dropped enough times to make something. Even
more, God had to create force. Before Him it couldn't even be
dropped. It would just float.

Nothingness just floated.

Just floated around long enough that eventually it became a bougainvillea.
Rediculous.

God is on people's hearts and in their minds. How can they deny Him? I
seriously do not understand.

But then what fascinates me more, is that in Jeremiah 31:31-34 when
God is talking about the new covenant he will make with the people,
and how He will write his law on people's hearts. Does this mean that
before Jesus came and fulfilled this, there wasn't an inherent
knowledge of the creator? God says they will no longer have to teach
one another about God because they will all know Him.

So people do know Him... do they really succeed in talking themselves
out of Him?