BERLIN — Ulrich Beck, a sociologist who became one of Germany’s most prominent public intellectuals by exploring the ways technology had created a new, riskier society, died on Thursday. He was 70.

The cause was a heart attack, family members told the German news media.

Mr. Beck shot to national and international fame in 1986 after the publication of his book “Risk Society: Towards a New Modernity,” which argued that one of humanity’s proudest achievements, technology, had also created new risks in spheres ranging from ecology to finance.

Technology, he said, created a new form of modernity that inherently involved more risk, or uncertainty, than the more rational Industrial Age. The book coincided with the world’s worst nuclear accident, at the Chernobyl nuclear power plant in Ukraine, lending it a currency that eventually led to the work’s being translated into 35 languages.

Still, Mr. Beck maintained a generally upbeat view as he tackled other contemporary topics. “What Is Globalization?” in 1997 and “Cosmopolitan Vision” in 2004 laid out what he viewed as the increasingly global nature of society, which he saw breeding a cosmopolitanism that could replace old thinking around national sovereignty.