Can you dig into that more and explain why it is so difficult to compare wealth across centuries? It would seem to me that you would just find some basic unit to divide against (a dozen eggs; a liter of milk; a sq kilometer of land), and then scale?

Whats wrong with my presumption? I know there must be quite a bit wrong with it, but I'm not familiar with economics whatsoever.

Because inflation doesn't take into account all the improvements that have been made. A liter of milk or a dozen eggs may almost be the same in 1630 and 2019. A square kilometer of farm land is not, since the crop yield today far exceeds that of 1630 (it has increased almost tenfold since 1930 due to mechanization, fertilizers and new grain types). So the same piece of land that could feed a family in 1930 now almost feeds 10 families. And, more importantly, land has many more applications now than back then: Factories, sky scrapers, airports, gardens, etc.

Take our homes. In the 1630s, homes had almost no insulation, no electricity, no central heat, no air conditioning, no shower, actually no running water, not even cold. The people who lived there inhaled smoke from the fireplace all day. They had no toilets or sewers, no internet, no cable TV or radio or cell phone connection. From evening until morning they sat in almost complete darkness since candles or oil lamps or whatever they used were crazy expensive. Houses weren't fire proof, barely water proof, wind proof or earth quake safe.

What I describe was true for the richest too. The very richest king or business owner in 1630 lived in a home, which fits my description. How do you even begin to compare his wealth to your wealth? 1,000 servants still couldn't bring him a tiny fraction of the comfort we enjoy. The very richest king in 1630 was dead poor compared to you. And that's just the material part. People were also exposed to crime in a way that we cannot even begin to imagine, and which you wouldn't even find today in our poorest neighborhoods. And their life would likely end decades before ours, and be a lot more painful. Even the richest business owner would not be able to stop his headache with a pill the way you or I can. Or tooth aches. Or fix a broken leg. A small wound could kill him. Most would see a number of their children die, maybe also wife in child birth.

Inflation numbers capture none of this.

im not sure i agree, the romans had running hot and cold water, onboard their luxury ships, not just in a house. so the richest king in 1630 probably had a lot more luxuries than you are giving credit for.

Also there were many simple remedies for things like headaches dating back to the BC years.

That would be the right approach to try, but essentially the problem is, if you want to try and compare wealth, then you have to do it without reference to the monetary unit. Even average working wage is tricky, because most people in that era didn't work for money - they lived off the land, possibly got paid annually with "in kind" payments of housing, food etc. as apprentices or servants.

The monetary unit is very misbehaved, still a problem today, and doesn't behave like other units of measurement. In particular between 1600 and today, you have fractional reserve banking coming in, and playing merry havoc with the money supply; whilst at the same time, the industrialisation that the banking system enables, rapidly increases production, and plays equal havoc with the amount of goods and services being produced. The former increases inflation, the latter reduces it.

If you turn the question round, and ask which company was more powerful - well the East India company and its competitors in their day opened up the sea lanes enabling the propagation of information and people around the world, for good and evil - and Apple and similar are doing exactly the same today. So they're certainly comparable, but simplistically asking which company is richer, is probably missing the point.

There are many problems, all interrelated.

First, how do you compare eggs? 1 egg cost X then Y now is one measure. A different measure is what % of an average person's wages did would it cost to buy the egg. Oh wait, the average person was a farmer who didn't buy eggs they went to the check coop to get them (even city folks are likely to have kept chickens): the only people buying eggs were rich who may not have paid real value prices. Then we have to ask what egg to compare to today - the common white egg, a brown egg, organic, pasture raised, a farm fresh egg delivered that morning...

Then there is efficiency improvements. Feed is cheap today because one farmer can raise thousands of acres of feed. Automation can feed millions of chickens in a barn...

Then there is supply and demand. A few years ago there was an avian bird flu epidemic and egg prices went up 3x over a matter of a few months and then back down. We know from history that there were famine years which would raise prices. Both of these factors exist outside of inflation and are sometimes not recorded well (do you remember the epidemic?)

Now take the above - any measure - and compare a liter of milk: the differences will not be the same.

That is just trying to compare Apples to Apples. However there is an additional problem: advancing technology. Today most on welfare (this limits us to rich countries, there are still villages of mud huts) have things like air conditioning and fast cars: luxuries that in the past the rich couldn't get any form of equivalent of. Then there are things where there was an analog but it was obviously inferior: TV (500 channels 24/7 as opposed to a live play), washing machines (the maids did laundry but the cost was much higher even if they were slaves)... That is the poor, middle class can afford airplanes trips once in a while.

And breeding, I wouldn't be surprised to see that a normal chicken egg is 3 times more heavy today, compared to the 17th century. Are we really still talking about the same product?