section_path: Principal works/Liber Primus Naturalium
section_name: Liber Primus Naturalium
paragraph_text: Liber Primus Naturalium
  
  Avicenna considered whether events like rare diseases or disorders have natural causes. He used the example of polydactyly to explain his perception that causal reasons exist for all medical events. This view of medical phenomena anticipated developments in the Enlightenment by seven centuries.