If I’ve got three sources that say the same thing then the statement they make is correct. Not necessarily. If source A, source B, and source C agree–do you know where source B and source C got their information? Did they get it from source A? If so, then you really don’t have three sources–you’ve got two sources that copied from another.<\/p>\n
It can’t always be done, but you want sources that were created independently of each other.<\/p>\n
An obituary, death certificate and tombstone agreeing about the date of birth doesn’t mean the information they provide about the date of birth is correct–it could mean they have the same informant.<\/p>\n