counterfactual

tosiasioiden vastainen contrary Contrary to the facts; untrue.
(quote-journal) (Review)|date=15 September 2014|passage=What would have happened if those great Chinese voyages by (w) had continued? It's one of those questions in counter-factual history about which it is impossible to be sure.
A claim, hypothesis, or other belief that is contrary to the facts.
puhekieltä A conditional statement in which the conditional clause is false, as "If I had arrived on time . . ."."http://www.philosophypages.com/dy/c9.htmcouf counterfactual" in A Dictionary of Philosophical Terms and Names (Garth Kemerling, 1997-2002)Random House Websters Unabridged Electronic Dictionary'' (1987-1996)
1952, B. J. Diggs, "VI.—Counterfactual Conditionals," Mind, vol. 61, no. 244, page 513:

In recent years there has been increasing discussion of the "problem of counterfactuals". One way of formulating this problem is as follows: "What is meant when one asserts a conditional statement, the antecedent of which is contrary to fact?"