What does "seem oneself" mean?

Question

"If truth be told, the Hand had not seemed quite himself for some times," Pycelle said.

I encountered this sentence from the Game of Throne. I have looked up the dictionaries and googled, but I cannot find the meaning of seem oneself. Does this whole sentence mean that what others said about the death of the Hand is not consistent with the characteristic of the Hand?

This whole paragraph is

"If truth be told, the Hand had not seemed quite himself for some times," Pycelle said. "We had sat together on council many a year, he and I, and the signs were there to read, but I put them down to the great burdens he had borne so faithfully for so long. Those broad shoulders were weighed down by all the cares of the realm, and more besides. His son was ever sickly, and his lady wife so anxious that she would scarcely let the boy out of here sight. It was enough to weary even a strong man, and the Lord Jon was not young. Small wonder if he seemed melancholy and tired. Or so I thought at the time. Yet now I am less certain." He gave a ponderous shake of his head.

Answer 1

Seem oneself should be understood from each word's meaning. The verb seem means:

Give the impression of being something or having a particular quality: it seemed a dismal town.

And oneself means:

In one’s normal and individual state of body or mind; not influenced by others:

[Oxford Online Dictionary]

"Not seemed quite himself" thus means:

He was not speaking, acting or behaving in a way that indicated his normal (usual) state of body or mind.

In other words, he was acting strange and he looked like going through changes in his body and mind.

Answer 2

You can find the meaning of the phrase "seem oneself" if you look up the reflexive pronoun yourself or himself in a dictionary.

If somebody looks to be in his normal physical or mental state,or he looks to be behaving as usual, you can say "He seems/looks himself".