Rinse and drain navy beans, watching and throwing out any small pebbles. Put in pressure cooker in 3 inches of water, without the lid. Bring to a boil and boil 5 minutes. Remove from burner. Put all in a separate pot for about 2 hours. Then drain beans and add fresh water.
While you are waiting for the beans to soften, pressure cook cottage ham butt according to size and directions on the label. Cool. Shred ham, removing the fat. Set aside.
Return beans to the pressure cooker with the fresh water, chopped onions, celery and shredded ham. Pressure cook about 20 minutes on full heat. Remove from stove, reduce pressure under cold water and open lid. Add salt, pepper, oregano, basil and bring to a boil. Should be ready to eat. If your beans are still too hard, pressure cook a little longer. You'll get used to your cooker and how long it takes depending on your stove top type. Best served with homemade baked cornbread (not sweet!) or fried cornbread patties.
This soup freezes beautifully. Just put desired serving size in freezer quart or gallon bags and freeze. Great to have on hand for a quick lunch or light supper on a cold winter day!