According to Enrique Peñalosa, the former mayor of Bogota, a sidewalk is not related to a street as much as it is related to a park. A street is all about transportation, movement from point to point. A sidewalk is much more than that. It is a public space; and a public space, to use Peñalosa's words, is...

“...for living, doing business, kissing, and playing. Its value can’t be measured with economics or mathematics; it must be felt with the soul... In my country, we are just learning that sidewalks are relatives of parks – not passing lanes for cars.”
A street has less soul than a sidewalk:
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