the real world is way too complicated for us to understand. economy is of the same nature.
we can look at different aspects of it though.

I didn’t do it before so I’ll define “Abstract” here.
in middle-school I did not learn what “abstract” means.
at uni in geometry I got an example:
look at the corner of a room. look at the stick of a broom.
what do they have in common? the aspect of a straight line!

to create the abstraction you just repeat their appearance right into infinity.
additionally you need to remove everything that isn’t a line.

it’s a filter that you apply, but it’s not a filter of vision.
it wont remove pixels or something.
instead you dissect how you think of these objects and cherry-pick a single aspect.

so when I use the word “aspect” above I really mean:
dissect how we think of it and find those aspects.
I really mean abstract thinking is getting used here.

one obvious aspect of economy is the money. but which currency?
internationally accepted is that all transactions are handled in USD.

not many decades ago it was gold. but money has the advantage you can create as much of it as you want.
well, the respective national bank can. they created the money in the first place.

another aspect of economy is jobs and workforce.
so, how is money related to jobs? by the wages of course.
but also by the fact that every worker also is a consumer.
so another interesting aspect of economy is the loss of jobs.
there are 2 possibilities: you lose a job because you were fired, or you quit.
right after losing a job, a new one wont be found that quickly, nor a replacement for the worker.
during that time consumption will be reduced. also the company will have less workforce available.
another problem for the company is that along with the workforce also knowledge is lost.

the worker who quit or was fired had experience with a particular set-up.
now the company could look for a worker with the same experience.
such a worker could have just been fired/quit from a competing company.
so one might think this would give the company new knowledge.

it is true that the competing company might have had better ideas.
such a new worker could contribute by introducing the best ideas.
but in reality, nobody will listen.
additionally economy tends towards monopolies, there likely are no competing companies.
and even if one could learn from one, doesn’t mean such knowledge really is useful.
companies always try to outperform  others by using  unique structures. structures found nowhere else.
same goes for the actual work-related knowledge. much too specialized to be useful.

in whole, it’s always a bad idea to rely on this kind of knowledge-gathering.
for example the insurance-adviser might bring some customers.
at the same time the person s/he’s replacing might have done the same for a competing company.
some customers might even get angry when the company fails to give them what only the previous worker knew they need.
same for a programmer working on a project. lot of time is lost with the replacement reading the old code.

knowledge is another important aspect of economy.
a company is only as knowledgeable as its workers.
universities or governments may do as much research as they want. wont help the company without the right workers.
there always must be someone who actually reads the research papers. someone who actually understands them.
in whole economy encompasses most parts of our lives, from school to retirement.
whenever we consume something or whenever we learn something new, we affect economy.

a job pays the worker. so s/he can consume.
a worker provides knowledge for the company. so it can outperform others with innovation.
a worker also provides workforce to it. so the company can produce for consumers.
to make things more complicated, the company has investments on stock-market and others.
additionally the company has debts and other ways of getting new investors for itself.
investors can be other companies or some workers, or indirectly some government, some country.
and debts in turn are again products that can be sold or protected by an insurance.
add to that the various currency variants and the various aspects of money and debts. you’ll get a model for economy.
however, a much better model should consider 2 more things:
resources and the “random” event of people losing or finding a job.
resources are finite. when they run low they become more expensive. also jobs and workforce are sort of resources.
people switching jobs have good reasons for that. so this probability distribution is quite constant per company.
the two fit in nicely with this model, so I’ll assume they are used too — although in real science of economy they aren’t.

now let’s take a look at knowledge and what it does affect.
knowledge is produced in school (not in the lab, there it merely gets discovered).
the reason is that it’s worthless when there is noone to acquire it.
but also the company does give knowledge to its workers.
in reality there is no such thing as “The Knowledge”.
there is always some underlying topic which makes each knowledge distinct.
when you learn something, you learn about several topics at once.
you don’t raise any mysterious IQ, you just know something new.
after some time has passed, the unused knowledge will become thinner. we just forget stuff. it’s easy to re-learn though.
a company would like to obtain knowledge along with the workforce. as a package.
with that knowledge a company can provide innovation.
innovation is a good reason for customers to switch their providers. although, it isn’t strong enough to convince all.
another kind of innovation is capable of making products cheaper or faster to produce.
in general a government might think that giving more knowledge to workers will increase taxes paid by companies.
sadly the loss of knowledge, caused by it being left unused, that loss makes this approach inefficient.
at first income might rise along with education, but eventually people just “know” too much.
what governments want is to raise innovation, but that’s something only the companies can do.
apart from many IT companies, usually the ideas of the workforce wont get through to the bosses.
additionally, whenever innovation makes a company richer, it’ll make another company poorer.
consumers wont just consume more because of better products, their money-resources are limited.

this all raises one question: is it possible to increase the total income of all countries simultaneously?
or is there a limit of how much tax-income can rise globally — without actually increasing the taxes?
how to increase that limit? what’s missing? are the approaches politicians currently use mathematically correct?