1. Learning indigo was a color in the rainbow. (pre-school)
This happened obviously when I was young, but this I always remembered as changing my perception of how I viewed the world. Up until this, I drew my rainbows with the colors that were available in my pack of eight Crayola crayons: red, orange, yellow, green, blue, violet. These were the colors we learned in preschool. But when I learned about ROYGBIV, it all changed. All of a sudden there was the magical other color which I had been ignoring for years, that I had not even been told about, and which Crayola had not even deemed important to be in the 8-pack, yet had been in rainbows all along! I had felt misled, and couldn't understand how such a critical color was lacking from crayon boxes, from people's general knowledge of colors. Additionally, I could not identify it in the common world. It seemed to have snuck secretly in there next to blue and purple, and was demanding mention.
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2. Learning pineapples grow from the ground. (college)
On a hike in Swaziland, we walked through a pineapple patch. When I noticed that the plants on the ground had pineapples growing from their centers, I was in shock. Up until now, I had pictured pineapples growing from trees, like apples, oranges, and peaches. Seeing them grow upward, from plants which looked like pineapple tops was life-altering. I would not have pegged them as growing this way, a secondary belief being that they probably could grow underground like radishes and carrots. To picture something happening in one manner for a long time, and then it being completely wrong, was eye-opening. I believe others could have this feeling when they discover bananas grow upwards, not downwards like you purchase in stores.
3. Learning you only breathe through one nostril at a time (post-college)
Through the nasal cycle, only one nostril is used at any given time. The nostrils switch off every two to four hours. I couldn't believe that I could go so many years without realizing this was happening! Testing it out, by feeling air blow out of only one nostril during normal breathing, left me speechless. (image source)
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