A Sophistical Argument

Great crane o'ertopping the delicate trees
Why do you seem so fair,
Swaying and raising your load with ease
High in the misty air?
You are a wonder of pearl and grey
Lifting strong arms to the sky.
Have you a meaning that's lovely, pray?
Why are you lovely, why?
I have a friend with a theory strange,
Thriftless in unity,
None of my reasons avails to change.
"Beauty is truth," says she.
Are you all ugliness, Fair-to-the-sense?
You are a symbol drear.
Though I should forfeit mine innocence,
Yet must I hold you dear.