Professor Nostradamus conducted an empirical or observed communications study in his laboratory where he convincingly found a connection between two variables.

The link concluded that Variable “X” always increased when the subject was exposed to Variable “Y”. By repeating the study over the course of several years he found the same results in his laboratory each time. What can he not say?

What do YOU think he can not conclude based on logic? We will be happy to comment after we read your answer.

I would say that Professor Nostradamus would not be able to say that his model or theoretical simplified version representation of the real world is an explanatory device, although it can be used to play an important suggestive role in the formulation of his theory. Any thoughts?

You did not address the question...The questions does not say anything about a simplified version representation of the real world.

The question is saying - after years of testing in his laboratory, he has found a consistent connection between two variables... What can he NOT SAY... what is missing in his study?

Can he not say that there isn't a connection between the two variables?

NO...he can't... the studies "in his laboratory" have shown a consistent contection.

What would have to be done to prove that the connection is consistent everywhere.

Further testing. But if he did the same test over and over, he concluded that others would get the same result. So could it be that others results might vary?

Yes, further testing...but there is one thing that can be done that would prove that the testing in "his lab" was valid....

The same tests under different conditions? Or using different subjects? I am lost on this one

RIGHT!!!! the tests have been consistent at HIS lab...to prove that his tests are valid , they would have to be done somewhere else by unbiased testers.... Then he could say that his tests were probably valid.