Meanings of own obtuseness in English

Derby knew this symptom well enough, but he had not the slightest idea that his own obtuseness was the cause.

And when the Philistines showed him in what manner they proposed to inflict their sentence he wondered at his own obtuseness.

His own obtuseness on the Bench was notorious, and had kept adding for thirty years to the Duchy's stock of harmless merriment.

There'd be some simple explanation, of course; something that would amaze him at his own obtuseness for not having seen it at once.

Darwin describes the phenomenon that a principle of divergence must resolve, and states his surprise at his own obtuseness before the fateful carriage ride:

'Calcott is teaching her his own obtuseness!'