On the question of city planning, the Houston Chronicle offers a fertile paradox:
Other research revealed the conditions that create pockets of poverty, and found a downside to ethnically mixed cities: People in different groups tend to live apart. “Here’s Mr. Diversity, extolling the virtues of diversity in large cities,” Florida says. “And what comes back to smash you over the head is that large diverse cities also incubate a horrific level of sorting and segregation.”
We must fix the way people are broken by forcing them to live together even if they do not want to. This requires us to assume that absolutely zero thought, or pure Biblical evil, went into their choices. In the meantime, everyone wants to live with people like them for the sake of comfort and enjoyment. This is because people befriend, work with, date and marry people who understand their worldview, most of which is genetic.
Silicon Valley, the 50 square miles of land in the US that has created more wealth than any other place in human history but has still achieved very little in becoming a more inclusive, truly diverse place.
Luckily, this problem is ending as the Silicon Valley bubble popped. SiVal was probably adding value to the economy up until the 2000s as it made tedious tasks more efficient, but since that time, it has been dedicated to producing more services which add no value and instead replace functional parts of the economy. When the bubble pops, many formerly useful functions will have to be rebuilt at a time when the economy is recapturing false value as losses. At that point, it will be unwise to walk in the city without looking up for falling bodies.