Googling is fun, and often instructive. But beware of translations. If the phrase  
is English, it's usually no problem. Even if the quote is a gloss, as in  
Hayek's of Tennyson, and maybe second hand at that, Google will get you  
close. If the quote is in another language, even just mostly correct, it's  
usually no problem either. (Try "Die Gedanken sind frei.") But if the quote  
you have is a translation from another language to English, beware, for you  
are at the mercy of translators, who often use the thesaurus as much as the  
dictionary, rarely use old dictionaries, much less historical dictionaries,  
and so often update and anglicize original meanings into something  
different from the original; then you're after a needle in a haystack. 
 
John Womack