CHICAGO — When Ella Shurin Soloveichik, the wife of renowned Torah scholar Rabbi Ahron Soloveichik, died two months ago, he told other family members that he felt as if half his soul had left him. So it was not entirely surprising that, after overcoming a debilitating stroke he suffered 18 years ago and continuing in his life's work — teaching Torah until the very end — Soloveichik himself died Oct. 4 after suffering a heart attack. He was 84.

Soloveichik was the founder and head of Yeshivas Brisk in Chicago and one of the world's foremost talmudic scholars and authorities on Jewish law. He taught Torah for 58 years, the last 34 in Chicago. Aside from his awe-inspiring scholarship, he was known for being a humble, kind man, yet one with an iron will: Although the stroke he suffered in 1983 left him partially paralyzed and in a wheelchair, he continued his duties as rosh yeshiva of Yeshivas Brisk and flew to New York every week to teach a Talmud class at Yeshiva University.

Soloveichik was born in western Russia in 1918 into a European rabbinic dynasty going back nine generations. His father, Moshe, was the chief rabbi of his town of Khaslavichy and a renowned scholar; his older brother, Rabbi Joseph B. Soloveichik, known simply as the Rav and considered the 20th century's leading rabbinic scholar, headed Yeshiva University in New York. Ahron Soloveichik's early teaching came from such Torah giants as the Chofetz Chaim, the Imrei Emmes and Rabbi Yitzhak Hutner.

The Soloveichik family moved first to Poland, then, in 1930, to the United States. Young Ahron Soloveichik graduated from Yeshiva College and received his rabbinic ordination, but found that he was having a hard time getting a job in New York. So he went to New York University Law School and graduated with a law degree in 1946. He spent the next 20 years teaching at yeshivot in New York.

In 1966, he came to Chicago to head the Hebrew Theological College in Skokie, a post he held until 1974, when he left to start Yeshivas Brisk. His wife Ella, a writer and teacher, was his partner in this endeavor, as well as in raising the couple's six children.

Soloveichik wrote two books in English, "Logic of the Heart, Logic of the Mind" and "The Warmth and the Light," as well as numerous Hebrew volumes.

It was as an interpreter of Jewish law that Soloveichik gained his greatest fame. "His scholarship was incredible," Rabbi Daniel Moscowitz, director of Chabad-Lubavitch of Illinois, said. He was able to take his vast Torah knowledge and apply it to modern-day questions. He was also a leader — someone who was not afraid to take stands on issues and to make his stands known to the public.

Indeed, those stands — always firmly rooted in Torah knowledge — were sometimes controversial. He was the only Orthodox rabbi in the country to oppose the Vietnam War, maintaining that fighting to save the world from communism was a fallacious goal.

He also differed from many of his peers in ruling that, based on Torah, brain death was not sufficient to certify that a person is dead. He was an outspoken opponent of the Oslo peace process, but he was also one of the few Orthodox rabbis in the world who blamed some in the Orthodox community for creating a climate of incitement that led to the assassination of Israeli Prime Minister Yitzhak Rabin.

But it may have been as a teacher that Soloveichik had his greatest influence, especially on Chicago's Jewish community.

Rabbi Asher Lopatin, spiritual leader of Anshe Sholom B'nai Israel Congregation in Chicago, knew and studied with Soloveichik from the time Lopatin was in high school. The younger man remained so close to his teacher that he would consult him on a weekly basis on various matters of Jewish law and interpretation, he said.

"He was my posek, my authority," said Lopatin. "I don't know who I'll look to now."

Lopatin said one of Soloveichik's greatest strengths was that he was able to come up with rulings that were firmly rooted in Jewish law but that worked for the modern world.

He was "a visionary whose rulings were far ahead of his times. For instance, he was ruling on matters concerning stem cells nearly a decade ago.

"He had a feel, an intuition for this world. His rulings can make a huge difference in people's lives. It was an amazing experience to be around him, to hear him give a ruling. He always gave them with such passion. Everything he did, he really did with passion."

Lopatin described Soloveichik as "a big patriot, very pro-American, a Hubert Humphrey-type liberal. He always voted Democratic."

Soloveichik is survived by six children. His four sons, all rabbis, are Moshe and Eliyahu of Chicago and Yosef and Chaim of Israel. His daughters, Rochel Marcus of Toronto and Tova Seigal of Newton, Mass., are both married to rabbis. He is also survived by two sisters in Jerusalem, almost 40 grandchildren and seven great-grandchildren. He was buried on the Mount of Olives in Jerusalem.