The phrase is often attributed to Shakespeare's *As You Like It*, where the character Jaques describes the seven ages of man:
> "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 school-boy, 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 honour, 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 slipper'd pantaloon,
> With spectacles on nose and pouch on side,
> His youthful hose, 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 sound. Last scene of all,
> That ends this strange eventful history,
> Is second childishness and mere oblivion,
> Sans teeth, sans eyes, sans taste, sans everything."
Here, "second childishness" represents the final stage of life, characterized by physical decline, memory loss, and a return to a childlike dependence.
While the phrase carries a certain sense of sadness, it's important to remember that aging is a natural process. Every individual experiences it differently, and it's crucial to approach the topic with sensitivity and respect.