This fleeting world

 ‘Thus you should think of this fleeting world: A star at dawn, a bubble in a stream; a flash of lightning in a summer cloud, a flickering lamp, a phantom and a dream’ - Diamond Sutra

Joseph Goldstein - Mindfulness

The world is a dream

It is discerning to behold the world as if it were a dream. You want to quickly wake up if you have a nightmare, and are relieved that it was only a dream. This world in which we exist now is no different.

Hagakure

Reality is much more complex for human understanding

HAMLET :
There are many things in heaven and earth, Horatio,
Than are dreamt of in your philosophy.

William Shakespeare - Hamlet
(The New Oxford Shakespeare - The Complete Works, Modern Critical Edition)

Hamlet. First soliloquy

O, that this too too sullied flesh would melt,
Thaw and resolve itself into a dew!
Or that the Everlasting had not fixed
His canon 'gainst self-slaughter. O God, God,
How weary, stale, flat and unprofitable,
Seem to me all the uses of this world!
Fie on't! ah fie! 'Tis an unweeded garden,
That grows to seed; things rank and gross in nature
Possess it merely. That it should come to thus:
But two months dead - nay, not so much, not two -
So excellent a king, that was, to this,
Hyperion to a satyr, so loving to my mother
That he might not beteem the winds of heaven
Visit her face too roughly - heaven and earth,
Must I remember? - why, she would hang on him,
As if increase of appetite had grown
By what it fed on; and yet, within a month -
Let me not think on't - Frailty, thy name is woman! -
A little month, or ere those shoes were old
With which she follow'd my poor father's body,
Like Niobe, all tears: - why she, even she -
O, God! a beast, that wants discourse of reason,
Would have mourn'd longer - married with my uncle,
My father's brother, but no more like my father
Than I to Hercules: within a month:
Ere yet the salt of most unrighteous tears
Had left the flushing in her galled eyes,
She married. O, most wicked speed, to post
With such dexterity to incestuous sheets!
It is not nor it cannot come to good.
But break, my heart; for I must hold my tongue.

William Shakespeare - Hamlet
(The New Oxford Shakespeare - The Complete Works, Modern Critical Edition)

All the world's a stage

All the world's a stage
And all the men and women merely players;
They have their exists and their entrances,
And one man in his time plays many parts,
His acts being seven ages. At first the infant,
Mewling and puking in the nurse's arms.
Then the whining schoolboy, with his satchel
And shining morning face, creeping like snail
Unwillingly to school. And then the lover,
Sighing like furnace, with a woeful ballad
Made to his mistress' eyebrow. Then a soldier,
Full of strange oaths and bearded like the pard,
Jealous in honor, sudden and quick in quarrel,
Seeking the bubble reputation
Even in the cannon's mouth. And then the justice,
In fair round belly with good capon lined,
With eyes severe and beard of formal cut,
Full of wise saws and modern instances.
And so he plays his part. The sixth age shifts
Into the lean and slippered pantaloon,
With spectacles on nose and pouch on side,
His youthful nose, well saved, a world too wide
For his shrunk shank, and his big manly voice,
Turning again toward childish treble, pipes
And whistles in his sounds. Last scene of all,
That ends this strange eventful history,
In second childishness and mere oblivion,
Sans teeth, sans eyes, sans taste, sans everything.

William Shakespeare - As you like it (II,7)