It is said that Beowulf excels at insights into people— what are some examples of this insight in the poem Beowulf?
In Beowulf, after the hero arrives, Unferth, the son of Ecglaf—a jealous man by nature, resentful of the attention being given to Beowulf—brings up a past adventure when Beowulf lost a swimming context with Breca. Unferth notes that Beowulf was bested in the challenge and that there is little hope for his success now with Grendel. Beowulf knows what is driving Unferth's words—so his response is bold and to the point:
What mighty things you've just said of Breca and his triumph, my dear Unferth, while you're drunk with beer!
Beowulf may be alluding to Unferth's poor and drunken manners in holding up Beowulf's "failure"—Beowulf is Hrothgar's honored guest. Unferth's comments are in bad taste, and Beowulf points this out, but he is also quick to clarify Unferth's mistake: Breca and Beowulf had, as young men, passed many "dares" between them. They entered the water together and swam side-by-side for five days until they were separated by the tide. Beowulf fought and killed nine sea monsters, while Breca made his way to land first. Beowulf claims his victory at sea, making him Breca's equal—regardless of what Unferth has said. Then he notes that Unferth has no room to talk of honor or victory—not only has he never accomplished what Beowulf has, but he murdered his own brother. Beowulf knows that Unferth is a coward.
We might also infer that when Beowulf, many years later, faces the dragon, he tells his men to stay behind perhaps because he realizes that he cannot depend on most of them—and his fate will be in God's hands. He tells his liegemen:
Now wait by the barrow, you in coats of mail and battle gear, to see which of the two of us will bear the wounds of this battle-rush better. Wait for the finish. This is not your fight, nor is it fitting for any but me alone to test my might against this monster here and achieve heroism. I shall win that wealth mightily, or war shall seize your king and lord with cruel killing!
As Beowulf goes into battle, the dragon's fiery breath is too much for the old hero, and his sword fails him. We learn that almost all his men—in his time of need—run away.
Alas, for his band of comrades, the sons of princes, did not stand armed about him with a battle-stance, but they ran off to the woods to save their lives.
However, one man will not leave his king. Beowulf will know the kind of man who stays: Wiglaf. The narrator speaks to the value of true "kinship:"
...true kinship can never be marred in a noble mind!
Wiglaf refuses to abandon Beowulf. He speaks to the others, and it is here that we might surmise that Beowulf could "read" the character of his men—even to Wiglaf, the only one who stands and fights. Wiglaf charges those who will not defend Beowulf:
This is why he chose us from among his army to aid him now; he spurred us on to glory and gave us these treasures because he counted us skilled warriors with the spear and brave beneath our helms.
Beowulf has no son or heir, so in choosing those who fought for him, he may have had an eye on Wiglaf, knowing that this honorable young man would value integrity over saving his own life.
Even though Wiglaf's shield is wooden (linden) and will not stand up to the fire of the dragon, Wiglaf enters the barrow where Beowulf is pinned down. He is not able to save Beowulf's life, but the old king and Wiglaf defeat the dragon and Beowulf passes his battle gear to Wiglaf as if he were Beowulf's son.