22/09/2015 06:39 BST | Updated 21/09/2016 06:12 BST

'Sonder' - (n) The Realisation That Each Passerby Has a Life as Vivid and Complex as Your Own

Today, like every day, I battled the insanity of the London underground at peak hour. Anyone who has experienced this will join me in a unanimous howl of frustration. You get pushed at, cut off, barraged, sworn at and generally harassed. I think more people would throw themselves in front of the train if their fellow commuters weren't so willing to help them onto the tracks. Sometimes, I think this is only happening to me, like I'm Jim Carrey in The Truman Show and the whole world is somehow clued in to the mechanisms plotting against me while I naively go along with it.

I paused for a moment on the platform as the trains rolled in and out, dispelling a cacophony of sound that can be heard solely underground. I felt deep sonder as I thought about the people milling around me, seemingly like cattle being herded down the narrow platform, but actually like humans. Humans, like me, who have thoughts and ideas, emotions and dreams. Humans with their own lives occupied by their own friends, family, fears and desires. As each person disappears from the periphery of my vision they are walking offstage of the production that is my life. I will never think about them again but little do I know that their day continues with the same gusto and vivacity as my own. They will go to their place of work, maybe get a Pret sandwich for lunch, complain about the commute, return homewards the same way they came and settle in for the night with a movie or a book. They will worry about bills, make jokes with their friends, fret over what to wear and wonder whether they will ever love again. And that night they will dream. Sometimes so vividly they can't discern between dream and reality.

2015-09-18-1442580714-8983439-sonder.jpgA few years ago I travelled around Spain with an old boyfriend, where this photo was taken. At the time we were wholly wrapped in the moment - playfully arguing over the perfect position and how to capture the most 'organic' snapshot. Only years later, when looking back at this photo, did I notice the couple in the background doing the same thing. For a while, I became obsessed with trying to figure them out. These people had an entire narrative of their own. Who were they, how did they meet, what was their story? In my limited imagination I could only envision them as a reflection of us, but a hundred times cooler - travelling the world on a motorbike and living off coffee, love and cigarettes. As they exited the frame of my picture, they exited the frame of my awareness and I'll never know what destiny awaited them. Whether life turned out the way they had hoped or whether they even stayed together. Whether they had any idea that one day a stranger would be sitting in a busy café in London and writing about them.

Some of us will cross paths and bottle a brief moment of each other's time. We will never capture another human being completely. We will never be able to embody their minds and understand the complexity of what it means to see the world through their eyes. To think that I am one person and I have so much feeling and compound energy that sometimes I feel like I might explode and there are billions of others just like me. Like a blanket of stars in a night sky, all seemingly identical to the naked eye but varied in brightness and shooting off in a billion different directions.

Visit Sasha's blog, where this post first appeared.