My key ring, with keys (!), small multitool, knife, AAA light, and small pry bar, is basic EDC and is handy even when I sleep. Around town, I have my wallet (cards, cash and ID), larger multitool, cell phone, and bandanna.

When in the woods, I always have a backpack with a decent FAK, canteen, and a"core bag," with the basic ten essentials (signalling, fire making, and shelter capabilities) along with whatever special gear the trip might require, like technical climbing items.

In the survival or near survival situations I have experienced,I have needed fire (for warmth and cooking), water (dehydration), and shelter (natural or improvised). While I had some sort of knie handy on those occasions, I don't recall the blade as being as critical as matches or spare, dry clothing.