Close your eyes and try to imagine an apple. Can you see anything? Aphantasia is the inability to see with your mind’s eye. Since it was discovered, scientists have been asking the question: What is the mind’s eye even for? This is the fifth episode of our six-part series, Making Sense. For more, go to http://vox.com/unexplainable It’s a great place to view show transcripts and read more about the topics on our show. Also, email us! unexplainable@vox.com We read every email. Support Unexplainable by making a financial contribution to Vox! bit.ly/givepodcasts Learn more about your ad choices. Visit podcastchoices.com/adchoices