(adjective) stubbornly persistent in wrongdoing / (adjective) hardened in feelings / (adjective) resistant to persuasion or softening influences
They are a close, loving family, and, given the tsar and tsarina’s obdurate myopia, they are utterly doomed.
The human mind's obdurate tendency to overconfidence becomes a major liability for humanity when the decision-making is delegated to tiny numbers of highly privileged minds.