Cities become more productive and efficient as they grow larger. It’s science. Cities play a crucial role in our evolution as a species. Statistics show that the bigger a city is the less pollution and crime there is within that city, and the more inventions and, ultimately, more opportunities for a healthier and more connected society. Despite the age old image that we have, that these cities are unnatural and accelerate crime, disease and waste: cities concentrate, accelerate and diversify social and economic activities.