Wealth is stuff people want.
A "wealthy" person owns economic engines that deliver this stuff to people who want it. How wealthy they are depends on the number of engines, how much stuff they produce, and how much this stuff is wanted.
Why is this relevant?
Because to avoid replacement, we need to understand what exactly is in danger of being replaced.
And the answer, put simply, is our jobs.
Most of the time, doctors work in exchange for money.
But it's really important to understand that money is not wealth.
It's just an intermediary. A way of transferring wealth from one specialised category to another.
When a lawyer gets a knee replacement, he doesn't pay the surgeon in tax returns. Instead, he turns his skill of writing tax returns into money, and then turns that money into a surgery.
This is a simple analogy, but it reveals another crucial idea:
An employee's "economic engine" lies in the rarity and usefulness of their skills. Some jobs (like a HR executive) are disconnected from the end user, and only indirectly make stuff people want, whereas others (like a carpenter) directly create wealth.
Doctors fall somewhere in the middle.
While they're reliant on external systems, their skills also let them deliver direct value to patients.
But these skills are at risk of automation.
We could argue all day about if/when doctors will be replaced. But when the downside risk is complete economic redundancy, I'd rather err on the side of caution.
And to do that, we first need a reality check.