Shakespeare wrote in the Tempest: "We are such stuff As dreams are made on." It turns he didn't originate the expression but built on it so that it became profound in its poetry. That's what Shakespeare seemed to do effortlessly.
Here is Prospero's speech:
And, like the baseless fabric of this vision,
The cloud-capp’d towers, the gorgeous palaces,
The solemn temples, the great globe itself,
Ye all which it inherit, shall dissolve
And, like this insubstantial pageant faded,
Leave not a rack behind. We are such stuff
As dreams are made on, and our little life
Is rounded with a sleep. Sir, I am vex’d;
Bear with my weakness; my, brain is troubled:
Be not disturb’d with my infirmity:
If you be pleased, retire into my cell
And there repose: a turn or two I’ll walk,
To still my beating mind.
Carl Sagan did the same - he turned it into this famous line: “we're made of star stuff,” and he continues with: "We are awake for the Cosmos to know itself."
Which stuff - the newer parts or the older ones? One scientific team has found that oxygen being a heavier element was synthesized earlier in the inner parts of the galaxy than in the outer parts, and that means that because are are composed of so much oxygen that we come from the oldest parts:
“It’s a great human interest story that we are now able to map the abundance of all of the major elements found in the human body across hundreds of thousands of stars in our Milky Way,” said Jennifer Johnson of The Ohio State University. “This allows us to place constraints on when and where in our galaxy life had the required elements to evolve, a sort ‘temporal Galactic habitable zone’”.
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