A smile from the past

We rush for the future
As if were a train,
As if it were a lottery ticket
Or a castle to live in,
 
It is a castle
Which is sometimes built on air,
On pillars of clouds,
 
There's no other way
But believe
 
We will have places and people to remember,
 
No other way to believe
There's a molecule of the future
Even in the past.