William Blake - What is the price of experience?

What is the price of experience?
Do men buy it for a song?
Or wisdom for a dance in the street?

No, it is bought with the price
Of all a man hath, his house, his wife, his children.
Wisdom is sold in the desolate market
where none come to buy,
And in the wither'd field
where the farmer plows for bread in vain.

It is an easy thing to triumph in the summer's sun
and in the vintage
and to sing on the waggon loaded with corn.
It is an easy thing to talk of prudence to the afflicted
To speak the laws of prudence to the houseless wanderer

To listen to the hungry raven's cry in wintry season
When the red blood is fill'd with wine
and with the marrow of lambs.
It is an easy thing to laugh at wrathful elements,
To hear the dog howl at the wintry door,
the ox in the slaughterhouse moan;
To see a god on every wind and a blessing on every blast;

To hear sounds of love in the thunder-storm
that destroys our enemies' house;
To rejoice in the blight that covers his field,
and the sickness that cuts off his children

While our olive and vine sing and laugh round our door,
and our children bring fruits and flowers.

Then the groan and the dolour are quite forgotten,
and the slave grinding at the mill,
And the captive in chains, and the poor in the prison,
and the soldier in the field
When the shatter'd bone hath laid him groaning
among the happier dead.

It is an easy thing to rejoice in the tents of prosperity:
Thus could I sing and thus rejoice:
but it is not so with me.