Friedrich Wohler heated ammonium cyanate and produced urea, an organic compound previously obtained only from living organisms. Working at the Polytechnic School in Berlin, he wrote to his mentor Jons Jacob Berzelius that he could make urea without needing a kidney. The synthesis demonstrated that organic and inorganic compounds obeyed identical chemical laws, undermining the doctrine of vitalism that posited a mysterious life force separating living and non-living chemistry. The experiment opened the path toward synthetic organic chemistry as a discipline.