Letters to the Editor Readers comment on penguin sex, math and more By Science News Staff January 26, 2020 at 7:00 am - More than 2 years ago Share this:Share Share via email (Opens in new window) Email Click to share on Facebook (Opens in new window) Facebook Click to share on Reddit (Opens in new window) Reddit Click to share on X (Opens in new window) X Click to print (Opens in new window) Print Math whiz In “How Julia Robinson helped define the limits of mathematical knowledge” (SN: 11/23/19, p. 22), Evelyn Lamb examined the life and career of mathematician Julia Robinson, who helped redefine the limits of mathematical knowledge. Readers had a lot to say about the story.