Yes you can - like eating the seeds of Oranges/mandarines/tangerines/etc, it won't be harmful.
However, it might not taste as good with the seeds as without, although that's a matter of preference - though because kumquats have a mixed tart/sour and sweet taste, you might not notice the taste of the seeds as much as you do when eating the seeds of the sweeter citruses like oranges.
Some popular recipes that feature the unique and delicious quince flavor include quince paste, quince jelly, quince tarts, and poached quince.
Quince quinientos quince milesimas
Quince = 15
Quince is fourteen in Spanish.
with a quince preserver
Quince Sugar
Quince in Spanish is "membrillo."
Louis Quince's birth name is Louis Veda Quince.
The Romanian word for quince is gutuie.
Quince Monitor was created in 1997.
Quince Duncan was born in 1940.
Peter Quince was created in 1596.