On the epistemological front, it has seemed to be an insuperable obstacle to moral realism to explain how, if there really were such a realm of moral facts, human beings could possibly gain access to it.
"We take no pleasure in ruling that the statute of limitations remains an insuperable obstacle to his effort to obtain adequate compensation for the brutality inflicted upon him 35 years ago," Judge Jon O. Newman wrote for the panel, which also included Chief Judge John M. Walker Jr. and Judge Amalya L. Kearse.
There may seem to be an insuperable obstacle to accepting Stein's relation R as representing a genuine relation of becoming.
The lack of strict laws covering events under mental descriptions is thus an insuperable barrier to any attempt to bring the mental within the framework of unified physical science.
Being an unknown actor on the verge of her 50th birthday ought to have been an insuperable obstacle to the ambitions for stardom Smith had held since childhood, but the director Mike Leigh liked to cast performers who did not distract the audience with instant recognisability.
"Political considerations must be put to one side," and parliament needed to be told of any "insuperable" obstacles to a break up.
"Dogmatism is an enemy to peace, and an insuperable barrier to democracy," he writes.
This is to portray institutional paralysis as an insuperable bar to enlargement.
Woolf tells Weaver that "the length is an insuperable difficulty to us", because "we can get no one to help us, and at our rate of progress a book of 300 pages would take at least two years to produce – which is, of course, out of the question for you or Mr Joyce".
"In most cases, I've chosen projects that have to do with an individual who has faced seemingly insuperable obstacles to deal with an extraordinary challenge," Mr. Johnson once said.
