Seeing is… well, seeing…
Via Discover‘s Bad Astronomy blog, one of the more amazing optical illusions that your correspondent has ever seen:
Alternating red and green spirals, right? Actually, they are exactly the same color. As Bad Astronomy explains,
The reason they look different colors is because our brain judges the color of an object by comparing it to surrounding colors. In this case, the stripes are not continuous as they appear at first glance. The orange stripes don’t go through the “blue” spiral, and the magenta ones don’t go through the “green” one. Here’s a zoom to make this more clear:
The orange stripes go through the “green” spiral but not the “blue” one. So without us even knowing it, our brains compare that spiral to the orange stripes, forcing it to think the spiral is green. The magenta stripes make the other part of the spiral look blue, even though they are exactly the same color.
As we reconsider the evidence of our eyes, we might recall that it ’twas on this date in 1852 (according to the stories) that Sherlock Holmes’ sidekick, Dr. John H. Watson, was born… while Holmes did occasionally say “Elementary!” (e.g., in “The Crooked Man”), he never actually said “Elementary, my dear Watson” to Dr. Watson in any of the stories/novels by Sir Arthur Conan Doyle. The phrase was actually a kind of homage, offered by P.G. Wodehouse, who first used it in Psmith Journalist in 1915; it found more common currency as it made it’s way into the scripts of the Sherlock Holmes films, perhaps most notably on the pursed lips of Basil Rathbone… Ironically, it was on this date in 1930 that Arthur Conan Doyle, Holmes’ creator, died.
Sir Arthur Conan Doyle (never actually seen in the room at the same time as Dr. Watson)