Okonkwo was popularly called the "Roaring Flame." As he looked into the log fire he recalled the name. He was a flaming fire. How then could he have begotten a son like Nwoye, degenerate and effeminate? [...]
He sighed heavily, and as if in sympathy the smoldering log also sighed. And immediately Okonkwo's eyes were opened and he saw the whole matter clearly. Living fire begets cold, impotent ash. He sighed again, deeply.

Chapter 17 (p. 143) - Things Fall Apart (1958)