At the age of forty the life you have lived so far, always pro tem, has for the first time become life itself, and this reappraisal swept away all dreams, destroyed all your notions that real life, the one that was meant to be, the great deeds you would perform, was somewhere else. When you were forty you realized it was all here, banal everyday life, fully formed, and it always would be unless you did something. Unless you took one last gamble.

Software development, like professional sports, has a way of making thirty-year-old men feel decrepit.

What most persons consider as virtue, after the age of 40 is simply a loss of energy.

I was so much older then; I'm younger than that now.

From the back pages

But I was so much older then, I'm younger than that now.

A poet more than thirty years old is simply an overgrown child.

On devient jeune à soixante ans. Malheureusement, c'est trop tard

When Hiro learned how to do this, way back fifteen years ago, a hacker could sit down and write an entire piece of software by himself. Now, that's no longer possible. Software comes out of factories, and hackers are, to a greater or lesser extent, assembly-line workers. Worse yet, they may become managers who never get to write any code themselves.

Only gradually did I realize that this lack of qualification could be an advantage. By the time most scientists have reached age thirty they are trapped by their own expertise. They have invested so much effort in one particular field that it is often extremely difficult, at that time in their careers, to make a radical change. I, on the other hand, knew nothing, except for a basic training in somewhat old-fashioned physics and mathematics and an ability to turn my hand to new things. I

There are books which one should not attempt before having passed the age of forty.

I used to think that eighty was a very old age. Now I am ninety. I do not think this any more. As long as you are able to admire and to love, you are young.

"My Back Pages"

Crimson flames tied through my ears
Rollin' high and mighty traps
Pounced with fire on flaming roads
Using ideas as my maps
"We'll meet on edges, soon," said I
Proud 'neath heated brow
Ah, but I was so much older then
I'm younger than that now.

Half-wracked prejudice leaped forth
"Rip down all hate," I screamed
Lies that life is black and white
Spoke from my skull, I dreamed
Romantic facts of musketeers
Foundationed deep, somehow
Ah, but I was so much older then
I'm younger than that now.

Girls' faces formed the forward path
From phony jealousy
To memorizing politics
Of ancient history
Flung down by corpse evangelists
Unthought of, though, somehow
Ah, but I was so much older then
I'm younger than that now.

A self-ordained professor's tongue
Too serious to fool
Spouted out that liberty
Is just equality in school
"Equality," I spoke their word
As if a wedding vow
Ah, but I was so much older then
I'm younger than that now.

In a soldier's stance, I aimed my hand
At the mongrel dogs who teach
Fearing not I'd become my enemy
In the instant that I preach
My existence led by confusion boats
Mutiny from stern to bow
Ah, but I was so much older then
I'm younger than that now.

Yes, my guard stood hard when abstract threats
Too noble to neglect
Deceived me into thinking
I had something to protect
Good and bad, I define these terms
Quite clear, no doubt, somehow
Ah, but I was so much older then
I'm younger than that now.

Bob Dylan, <i>Another Side of Bob Dylan</i> (1964)

As you can hear, it’s difficult to learn another language after forty.

A man who views the world the same at fifty as he did at twenty has wasted thirty years of his life.