system
Given the following post, respond as if you're commenting on Reddit:
human
[LOTR] Independent thought in the Nazgul

How much independent thought/problem solving ability do the Nazgul have? The Witch King must have needed a lot of it to do all the Angmar stuff but can't such ability result in plotting against Sauron to regain the Nine or One Ring?
gpt
He certainly still has his own thoughts and feelings, but feels (and fears) the ever present ensalving will of Sauron (during the Third Age Sauron took the Nazgul's Rings from them, so that he could control them while he was without the One).

Below is one of the few glimpses we get into the psyche of the Witch-King, describing the events of of Weathertop and immediately after.

> The camp is attacked by night by five Riders; but they are driven off by Aragorn; and withdraw after wounding Frodo. The Witch-King now knows who is the Bearer, and is greatly puzzled that it should be a small creature, and not Aragorn, who seems to be a great power though apparently 'only a Ranger'. But the Bearer has been marked with the Knife and (he thinks) cannot last more than a day or two.

>It is a strange thing that the camp was not watched while darkness lasted of the night Oct. 6-7, and the crossing of the Road into the southward lands seems not to have been observed, so that the Witch-king again lost track of the Ring. For this there were probably several reasons, the least to be expected being the most important, namely that [the Witch-King], the great captain, was actually dismayed. He had been shaken by the fire of Gandalf, and began to perceive that the mission on which Sauron had sent him was one of great peril to himself both by the way, and on his return to his Master (if unsuccessful); and he had been doing ill, so far achieving nothing save rousing the power of the Wise and directing them to the Ring. But above all the timid and terrified Bearer had resisted him, had dared to strike at him with an enchanted sword made by his own enemies long ago for his destruction. Narrowly it has missed him. How he had come by it - save in the Barrows of Cardolan. Then he was in some way mightier than the Barrow-Wight; and he called on Elbereth, a name of terror to the Nazgûl. He was the in league with the High Elves of the Havens.

>Escaping a wound that would have been as deadly to him as the Mordor-knife to Frodo (as was proved in the end) he withdrew and hid for a while, out of doubt and fear both of Aragorn and especially of Frodo. But fear of Sauron, and the forces of Sauron's will was the stronger.    
~ "The Hunt for the Ring"