I want to know the answer to the following question:
Which theory did the law of conservation of mass disagree with?
All the background I'm provided with is that "Other important steps included the gravimetric experimental practices of medical chemists like William Cullen, Joseph Black, Torbern Bergman and Pierre Macquer and through the work of Antoine Lavoisier (Father of Modern Chemistry) on oxygen and the law of conservation of mass, which refuted phlogiston theory.". Is that enough to answer the question?
Answer: yes