"It Couldn't Be Done", written by Edgar A. Guest, was first published in 1914 in his poetry compilation Breakfast Table Chat. This particular poem has an 'ababcdcd' rhythm. "It Couldn't Be Done" is widely considered to be Edgar A. Guest's best-known poem.
On a more personal note, I really don't go in for 'inspirational' stuff, but I happen to really like this poem. I feel that its optimism is uplifting without being cheezy.
Somebody said that it couldn't be done,
But he with a chuckle replied
That "maybe it couldn't," but he would be one
Who wouldn't say so till he tried.
So he buckled right in with the trace of a grin
On his face. If he worried he hid it.
He started to sing as he tackled the thing
That couldn't be done, and he did it!
Somebody scoffed: "Oh, you'll never do that;
At least no one ever has done it";
But he took off his coat and he took off his hat
And the first thing we knew he'd begun it.
With a lift of his chin and a bit of a grin,
Without any doubting or quiddit*,
He started to sing as he tackled the thing
That couldn't be done, and he did it.
There are thousands to tell you it cannot be done,
There are thousands to prophesy failure;
There are thousands to point out to you one by one
The dangers that wait to assail you.
But just buckle in with a bit of a grin,
Just take off your coat and go to it;
Just start to sing as you tackle the thing
That "cannot be done," and you'll do it.
-- © 1914 Edgar A. Guest
*quiddit=quiddity, subtlety
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