Simon Cowell Unleashes on... Simon Cowell

Music industry mogul and "American Idol" judge Simon Cowell has unleashed his infamously sharp tongue on a new, unlikely target: himself.

In a letter published in the British newspaper the Daily Mail Cowell subjects himself to the same harsh criticisms he's showered upon hundreds of "Idol" contestants.

"Look at you. You look like a complete idiot... You are overconfident, far too cocky and dressed from head to toe in expensive designer gear," Cowell writes to a younger version of himself. "Stop it, Simon. This is embarrassing. You are making me cringe."

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The self-addressed letter, a retrospective that alternately lashes out at and encourages his younger self, chronicles Cowell's meteoric, yet short-lived initial success in the music industry, the sobering big crash that followed and his eventual return and unprecedented success.

The revealing reflections, entitled "A Letter to My Shallow, Reckless, Cocky Younger Self," come as "American Idol" judge's 50th birthday looms on Oct. 7.

Cowell is especially critical of the 1980s version of himself, the one that drove a Porsche, wore expensive clothes and went to elite restaurants and nightclubs, all the while unable to appreciate it all and much less able to afford it, Cowell writes.

"For two or three years you have earned nothing of substance but you have racked up debts of nearly half a million quid. On what? On junk," Cowell writes. "Suddenly it all grinds to a halt. It's over!"

Under a mountain of debt, Cowell moved back in with his parents. Oddly, Cowell said he felt his personal crash was a "huge relief."

"Yet the funny thing is, what you don't know, Simon, is that you will never again feel so carefree in your entire life," he writes.