Two, usually, for EDC. A Vic SD Classic SAK on the keyring. And either a black SAK Swiss Champ or lighter SAK Explorer in pocket.
If hiking/camping/boating, 3 or 4. The Champ plus a backup Champ plus a 111mm SAK Fireman with the larger locking blade/serrated/saw combo. And if longer than a dayhike then a larger fixed blade, 7" KaBar USMC or Ontario SP1. Good general utility/firewood knives.
Over the years I have learned to value redundancy. Backup knives, backup headlamps, backup fire sources.