He should see the dead man's face by day and night as long as he lived.
This forced conclusion was in logical accordance with his original nature and developed character, for it was the result of that economical, cautious disposition which foresees the consequences of action and guides itself accordingly.

Even in the moment when he had nearly killed Paolo that morning he had not been free from this tendency.

In the instant when he had raised the tool to strike he had thought of the means of disposing of the body and of hindering suspicion.

The panorama of coming circumstances had presented itself to his mind with the rapidity of a flash of lightning, but in that infinitesimal duration of time Paolo had turned round, and the opportunity was gone.

His mind had worked quickly, but it had not gone to the end of its reasoning.