At a minimum TWO...most of the time four:
Kershaw Leek in front left pocket for everyday mundane tasks....& defensive use with left hand if needed.
Spyderco 'waved' Endura in front right pocket.
Strider SNG in sheath on belt (weak side) next to magazine pouch & Surefire light.
Kershaw Chive or another Leek in neck sheath