Sentence examples similar to impregnable mind from inspiring English sources

The character and the ancestry of mental fashion become more difficult to detect as it increases its power and its pretensions by annexing "better," previously impregnable departments of society, and converting "more serious," formerly independent minds.

An impregnable theory, or one nearing the limit of impregnability, is in fact as great an absurdity as an impregnable armour-plate.

An impregnable assertion.

Is that defence impregnable?

The enigma seems impregnable.

"Bell Canada is impregnable".

To many, Google appears impregnable.

The Confederate entrenchment was impregnable.

The death penalty seemed impregnable.

"Impregnable" was an autoantonym, too.

No system, however, is impregnable.