To keep in spirit with the whole 'Wiki'-idea I suggest you keep everything as open as possible, within the limits of privacy offcourse.
The default for profiles of non-living people under 200 years old is 'Public', unless they are added as the nuclear relative of a living person.
Anyone can view the information on a Public profile. However, even though anyone can view a Public profile you still need to be in the Trusted List to add or change information.
You can find more information on Privacy here.