HUGO CHAVEZ loves to talk. Since he became Venezuela’s ruler in 1999, according to one count, he has appeared on national television 2,135 times, for an average of 43 minutes per day. So one sure sign that there is something odd about Mr. Chavez’s prolonged stay in a Cuban hospital is this: He has been heard from only once since he checked in on June 10, and that was more than two weeks ago.

A second oddity is the failure of Mr. Chavez or anyone else in his government to explain what is wrong with him. Mr. Chavez underwent what was described as knee surgery in May; his operation in Cuba was said to be in response to a pelvic abscess, which is a buildup of pus that can have various causes. As weeks have passed without Mr. Chavez returning to Caracas or speaking in public, Venezuela’s remaining free media have been filled with increasingly detailed speculation about his underlying illness — with prostate cancer emerging as a favorite theory.

The most concerning signals, however, have come from Mr. Chavez’s older brother, Adnan, a provincial governor. After visiting the caudillo last week, the elder Chavez first announced that he would return to Venezuela in 10 to 12 days. Then, at a prayer service last weekend, Adnan Chavez abruptly declared that while it was good that the “revolution” had “made it through elections” so far, the regime’s supporters could not rule out “armed struggle.” This has raised some obvious questions in a country dominated by one man for more than a decade: Was Adnan Chavez positioning himself to succeed his brother, in the fashion of Raul and Fidel Castro? Was he suggesting that the incapacitation of Hugo Chavez could lead to the use of force by his followers?

Chances are that Hugo Chavez will stage a triumphant return before the July 5 celebration of the 200th anniversary of Venezuela’s independence. But the episode has underlined the growing instability in a country that supplies 10 percent of U.S. oil imports. While Mr. Chavez has been incommunicado, troops have struggled to regain control of a large prison taken over by armed inmates; at least 25 deaths have been reported. Power outages are plaguing the cities again, the murder rate is worse than in Mexico or Iraq, and inflation, at 23 percent, is the highest in the world. Having concentrated power in his own hands, Mr. Chavez governs a nation that is spiraling beyond anyone’s control.

There was, however, one positive news item this week: Venezuelan bond yields, which also are among the highest in the world, suddenly dropped. Apparently some speculators are betting that Mr. Chavez’s health problems will drive him from office — and consequently are projecting a more positive future for the country.