Like many scientists and engineers I deal with very large and very small numbers daily. Sometimes, though, it is easy to lose perspective. Whenever I want to get a more visceral grasp on the relative size of something I make a similar ratio using stuff from the everyday world.
Consider money. You can map quantities of currency onto scalar distance to get a feel for just what constitutes a lot of money. Suppose one US dollar is equivalent to half of an inch. That’s a little less than the diameter of a dime or about the diameter of a AA battery. So $1000 would be 500 inches or a little over 40 feet (nearly 13 meters).
What’s a lot of money for most folks? How about one million dollars? It’s about 20 times the median annual household income in the US and noticeably larger than the “nest egg” most people hope to retire on. Well, a million dollars equates to roughly eight miles in this scheme. A dime versus eight miles. Pretty big, right?
Contrast this to a billion dollars. A billion dollars is roughly the diameter of the Earth. So, think of how wide a dime is and then think of how wide the Earth is. That’s a billion to one ratio. Now there are people on this planet Earth who are billionaires. For example, the Koch brothers and several members of the Walton (Walmart) family are each worth in the neighborhood of 20 billion dollars. That’s 20 or more Earths lined up side-by-side. In comparison, if you have $100,000 in the bank, that’s equivalent to about 1400 yards.
At this point it is worth noting that the Supreme Court has pretty much said that money equates to free speech. So how loud do you think your voice is now?