Tamasic fortitude works in the wrong direction. Instead of holding steady toward something worthwhile, it clings to the very things a person should release: excessive sleep, fear, grief, despondency, and arrogance.
This is not strength — it is inertia. Imagine a person gripping a heavy stone while drowning, refusing to let it go. The grip is firm, the hold is real. But it pulls them deeper. That is tamasic dhriti: steadfast attachment to what harms.
The person of dull understanding does not release these burdens because they cannot see them as burdens. Sleep feels like rest. Fear feels like caution. Grief feels like loyalty. Each one wears a disguise, and tamasic fortitude keeps the disguise in place.