http://z5lcip4dafatwwa6hvyibizpzwycvwp67cjga3hzjhxhwvuyaqavxnid.onion/mind/recent
There are people (not me) who, when they think of 5, see the color red. Could it be that redness is just the number 5, but my brain lacks the ability to see the connection between the two? Granted, not every synesthete sees 5 as red, but perhaps they're internally experiencing the same color as someone who sees 5 as red and have learned to call it green...