Organon §140

If the prover cannot write, the physician should interview him daily as to what may have happened to him and how. For the most part, it should be a solely voluntary account of the prover. Nothing that is written down as findings should be guessed at, nothing supposed, and as little as possible should be pumped out of the prover. Everything must be done with the same caution I have indicated above on case-taking and finding out about the image of natural diseases (§84-§99).