
Writing in Appendix N, AD&D Dungeon Masters Guide (1979), p. 224
The Honolulu Advertiser (20 June 1959) https://www.newspapers.com/image/259239643/?terms=Pogo, cited in "Pogo on intelligent life in the universe" by Garson O'Toole, in Archive of the American Dialect Society listserver (16 February 2017) http://listserv.linguistlist.org/pipermail/ads-l/2017-February/146520.html, and in 'Pogo Comic on Extraterrestrials: Either Way, It’s a Mighty Soberin’ Thought", The Quote Investigator (18 February 2017) http://quoteinvestigator.com/2017/02/18/space/. This has often been paraphrased as: "Thar’s only two possibilities: Thar is life out there in the universe which is smarter than we are, or we’re the most intelligent life in the universe. Either way, it’s a mighty sobering thought."
Pogo comic strip (1948 - 1975), Porky Pine
Writing in Appendix N, AD&D Dungeon Masters Guide (1979), p. 224
“Maybe if I point to my brain it will work.”
http://www.thelivingend.info/band/chris-cheney.php
Source: I Lived to Tell It All (1996, ebook 2014), Page 205.
Quoted in Remembrance by Tom Johnson (September 1987)