When I want to discover something, I begin by reading up everything that has been done along that line in the past — that's what all these books in the library are for. I see what has been accomplished at great labor and expense in the past. I gather the data of many thousands of experiments as a starting point, and then I make a thousand more.

In: Dogbert D. Runes (ed.), The Diary and Sundry Observations of Thomas Alva Edison - Chapter XXVII (pp. 161-162)