Progress and progression. What is the difference between them?

Could you please help me differentiate between those two words? I give two examples below to use for discussion.

e.g. ... career progression (what I see in the Oxford dictionary),

... career progress (my own example)

Drugs can slow down the progression of the disease.

OR

Drugs can slow down the progress of the disease.

Solution 1:

The difference is subtle. Many times they will overlap in meaning. Your "drugs"sentences are examples of such overlap. To me, both sentences mean exactly the same thing. The "career" sentences maybe have some slight difference of nuance.

To address those differences, "progress" is a state in which something is moving from one state to another, whereas "progression" tends to refer to whether such progress is actually possible, i.e., whether progress is a factor.

For example:

"There is no progress" means that the subject has not changed from its current state. It is something of a subjective statement, reflecting the speaker's perception. For example, "career progress" is something that people generally consider to be a good thing, and a lack of it could well draw judgment.

On the other hand, "There is no progression" would be used more in describing a subject (such as a system) in which progress is not a factor. It is an objective statement reflecting the way something is constituted. For example, it could be a comment on an academic curriculum made up of individual courses, the completion of any one of which does not necessarily lead to beginning another one.

I don't think "progression" would be used much in describing the state of someone's career; "progress" would be the more common term. But if you were talking generally about how people are promoted (i.e., about the system by which people progress in their careers), it could be used such as in "There is a progression from shop floor worker, to foreman, to manager." (In a sentence like this, you certainly wouldn't say "a progress from A to B to C.")