… Should somebody here whip out his lead pencil in order to note on the margin of the page that no such immiscibility attaches to the subjects of the fruitfulness of observations and that [of] reasonings, I hope he will pause long enough to reflect that I can hardly be supposed to have selected the unusual word “uberty” instead of “fruitfulness” merely because it is spelled with half as many letters. Observations may be as fruitful as you will, but they cannot be said to be gravid with young truth in the sense in which reasoning may be, not because of the nature of the subject it considers, but because of the manner in which it is supported by the ratiocinative instinct.
http://www.commens.org/dictionary/entry/quote-essay-toward-improving-our-reasoning-security-and-uberty