Oft turning others' leaves to see if thence would flow
Some fresh and fruitful flower upon my sunburned brain.
But words came halting forth ...
Biting my truant pen, beating myself for spite,
'Fool,' said my muse to me, 'look in thy heart and write.'"

And though he turned others' leaves it was quite literally looking in
his heart that he wrote. He analyses the sequence of his feelings with a
vividness and minuteness which assure us of their truth. All that he
tells is the fruit of experience, dearly bought:

"Desire! desire! I have too dearly bought
With price of mangled mind thy worthless ware.
Too long, too long! asleep thou hast me brought,
Who shouldst my mind to higher things prepare."

and earlier in the sequence--

"I now have learned love right and learned even so
As those that being poisoned poison know."

In the last two sonnets, with crowning truth and pathos he renounces
earthly love which reaches but to dust, and which because it fades
brings but fading pleasure:

"Then farewell, world! Thy uttermost I see.
Eternal love, maintain thy life in me."

The sonnets were published after Sidney's death, and it is certain that
like Shakespeare's they were never intended for publication at all. The