Quote by Galileo Galilei

Long experience has taught me this about the status of mankind with regard to matters requiring thought: the less people know and understand about them, the more positively they attempt to argue concerning them, while on the other hand to know and understand a multitude of things renders men cautious in passing judgement upon anything new.

Please suggest source details if you know: book, page, year, online article address (url), correction (different author...), etc.. Thanks.