a question that you sometimes need to ask yourself when doing worldbuilding: how much of the world is 20% of it? that's 1 in 5. how many people do you know, either personally or in passing, like the cashiers at the grocery store near your house? how many of these people would have a condition if it was 1 in 5 of them? how about 25%? that's 1 in 4. is this as uncommon as you are positing it is? how much do you think even 1% of the global population is? how many hundreds of people do you pass by on the streets, or in a grocery store, or drive past in your car in a month?











