* There are many biographies of Hypatia. You need to specify the author of the biography you are comparing to the Joyner biography. There are well-known biographies by Maria Dzielska and by David Kingsley, for example.
* Primary sources on Hypatia are scarce. Hypatia lived in the 4th and 5th centuries, and very few primary sources survive from that period. Most of what we know about her comes from secondary sources, often written long after her death and potentially biased.
* "Joyner biography" is ambiguous. This could refer to any number of biographies written by authors named Joyner. You need to provide the author's full name.
To get a more accurate comparison, please provide the full names of the authors and titles of the specific biographies you're interested in.
Once you do, it might be possible to compare the number of primary sources used in each book. However, keep in mind that:
* Quantity doesn't always equal quality. A biography with a few well-chosen, reliable primary sources might be more accurate than one with many questionable primary sources.
* Both biographies might rely heavily on secondary sources. This is common in historical biographies, especially when dealing with figures from the distant past.
Ultimately, the best way to judge the quality of a biography is to consider its overall scholarship, its use of evidence, and the author's interpretation of the available data.