Evolution's quirks - Lists

Today you'll probably use Evernote, Apple's Notes or some other scribbling application. Here's a question : Where does the impulse to jot down ideas come from ? How come we're concerned by our forgetfulness ? 

I perceive value, I confer value, I create value, I even create – or guarantee – existence. Hence, my compulsion to make “lists.” The things (Beethoven’s music, movies, business firms) won’t exist unless I signify my interest in them by at least noting down their names.

Nothing exists unless I maintain it (by my interest, or my potential interest). This is an ultimate, mostly subliminal anxiety. Hence, I must remain always, both in principle + actively, interested in everything. Taking all of knowledge as my province

Susan Sontag

The word, its ideas and its products, won't exist in our perception unless we shine the spotlight of our interest upon them. Unless we witness them.

Or is it the case ? "If a tree falls in a forest and no one is around to hear it, does it make a sound?" Can something exist without being perceived? e.g."Is sound only sound if a person hears it?"

The fact we make lists means we believe the answer is "No". Lists are our daily way of making sure Existence ... Exists !