Editor's note

Actually, you can note down your personal questions, opinions or interpretations or unproven "conclusions" about the culture. However, they should be clearly identified as such, so you don't treat them as field data.

They are useful for helping your understanding grow and for finding new lines of investigation. You will usually want to turn them into questions at the first opportunity.

You will notice that the "facts - all the facts and nothing but the facts" are in fact interpretations. At first, you don't know what is important and what isn't, and you may be unable to identify objects and activities using the same categories that local people use. As your progress, your "facts" will improve.