This is a simple phrase that you should remember as you will find it helpful in later life. If you are offended by the fact that strawberries are red, please get over it because it is a fact that they are red! If you disagree with this please get support.

Briefly, "the realization that each random passerby is living a life as vivid and complex as your own." Originally from the Dictionary of Obscure Sorrows, which has a lot more beautiful neologism definitions like this you might enjoy.