Explain why there is no universal standard for what qualifies as a city.

The reason there is no universal standard for what qualifies as a city can be broken down into several steps:

1. Different Definitions: The definition of a city varies from country to country. In some places, a city is defined by its population size, while in others, it's defined by the presence of certain institutions or services, like a cathedral or a university.

2. Cultural Differences: The cultural context also plays a role in defining what a city is. For example, in some cultures, a city might be considered a large, bustling metropolis, while in others, a city might be a small, quiet place with a tight-knit community.

3. Historical Context: The historical context is also important. Some places might be considered cities because they were important centers of trade or power in the past, even if they're not particularly large or busy today.

4. Legal Definitions: In many countries, the status of a city is determined by law. This means that a place can become a city (or stop being a city) if the law changes.

5. Geographical Factors: Geographical factors can also influence what is considered a city. For example, in densely populated countries, a city might need to have a larger population to be considered a city than in less densely populated countries.

In conclusion, the lack of a universal standard for what qualifies as a city is due to a combination of different definitions, cultural and historical contexts, legal definitions, and geographical factors.