Good Question

One day the Doctor and I were walking along a busy street. It was rush hour. People were in a hurry.
Suddenly he stopped me and stared at me intently.
I was very aware of the roadblock we formed but I could not get myself to move out of the way.
He asked me to close my eyes and open my mind a little.

"Imagine yourself at the end of a stressful day." he said. "You're running, maybe you feel hunted or you are short of time. Maybe you are lost, or late, or both."
"You slept badly the night before and now you're really, really tired. Your muscles ache and your feet burn. It's been a long day."

He paused and I noticed I actually did feel tired.
Such days are not too hard to imagine. We all know what those days can be like!

"But now that day is almost over", he continued, "and you know of a secret passageway, just a small door that only you know about and through which you can slip unnoticed."
"On the other side of that door is your safe place, where you can enjoy some peace and the possibility of relaxation."
"In fact, you are almost there...you arrive at your safe place, where you feel comfort and safety... You open that door... Tell me what does that pleasant place look like?"

With my eyes still closed I described my soft and safe surroundings. I could see rolling hills of luscious green. I heard the singing of birds over the gentle rustling of leaves on large trees gently swaying in the cool evening breeze.

Then he asked me to open my eyes and look around.
Rush hour... a busy street. People were passing us left and right.
Reality was noisy and not at all like my imaginary paradise.

"Nobody ever mentions stone or concrete and steel and glass or the sound of howling metal when I ask that question.", he said.
"So why do we live in a world built like that?"