I agree with the original post. I also agree with the insightful comments thereafter. I understand it's a catchy phrase to reinforce the concept of redundancy. I get that.

However, here's why I agree with the original post as well. The beginning part of the phrase is too much hyperbole, specifically, "one is none." If that's true, what is "none?" For example, if I have one good fire starter in my bag, is that practically the same as having zero good fire starters in my bag? No, that's ridiculous. The comparison is not even close.

Let's use concrete numbers for you logical folks. Having one good fire starter equals a score of about 90%. Having two good fire starters equals a score of about 98%. Having zero good fire starters equals a score of 0%. So, you get an A- for one good fire starter and an A+ for two good fire starters. You are beyond failing if you have zero good fire starters.

For those of us who already understand the value of redundancy when it comes to packing stuff, one is one, and two is two.

I think I would interpret the saying in more black and white terms, instead of gradations like 90% versus 98%. Like pass/fail.

Having none of some critical item is obviously a fail. Having just one item is either a pass or fail, depending on which side of Murphy's Law you happen to fall on in any given situation. But if a critical "fail" can be avoided by having a backup, then it seems only logical to do that.

Of course, it is overkill to apply the saying to every single item in your kit, and there, I wholeheartedly agree that the "math" doesn't add up. And having five of an item is not necessarily any more helpful than two of something, or perhaps not even necessary at all. I may survive some situation just fine without a bandana, let alone five bandanas, say.

"One is None" could be discouraging for those new to prepping/self-reliance. Not to mention us addicts, who can easily decipher it to mean we need four of everything. I never thought of it that way before today.

Dave Canterbury (who I think gets credit for this motto) has a more specialized audience than your run of the mill, Red Cross/FEMA says I should get everything on this list to be be prepared for 72 hours person, but Discovery and the ubiquitous YouTube have probably broadened his viewership.

To his credit, DC advocates for the 5 Cs of survivability first (Cutting, Cordage, Container, Combustion and Cover), then 5 more. (The 10 Cs, which I can't remember because I don't think in those terms.) It seems that only after his 10 Cs are met, does he suggest redundancy. In my mind, this says get your basics covered first, and then worry about adding more. That gets lost in the face of his oft repeated "One is none and two is one" motto.

A good example is the "Survival Summary" thread. Worrying about multiple redundancies (in that case weapons) makes no sense until you've got all your other necessities covered.

http://forums.equipped.org/ubbthreads.php?ubb=showflat&Number=258980#Post258980).

That said, you have to know your own abilities. I watched Myke Hawk survive in the Amazon with just a machete and thought two things:

1. The other guy that was forced to try it and lost his machete, probably should have had a backup. Myke would be better off with a backup too, just in case it breaks or something.

2. I could never do that. If I ever go, I'm taking everything I need, and backups for the most important stuff, kept on my body as well as in my pack.

One is none if one breaks. And if you are ultralite, you may be SOL in that case.

In the interests of weight, I carry a folding knife and a Leatherman. I carry a lighter and a ferro rod. I carry a Maglite, and a windup radio/light/siren combo (covers 3 areas).

I don't carry a backup for everything, just the important stuff.

Redundancy makes sense in some situations. For years, the standard for cavers has been three independent light sources of light. In a cavern, being without light basically means you can do nothing - the darkness is complete. Like many posters here, I also agree that redundancy in fire making often makes sense. Fire is critical and the means of ignition are rather light and easy to carry

I have usually seen the "one is none" routine applied to guns and knives, where it is just plain silly, seemingly an excuse to sell one more firearm and one more blade.

When I prepare for a backpack or a climb, I adopt the principle of "elegance" -I want critical and necessary items, but nothing in excess - the weight penalty is prohibitive. Multipurpose items are quite handy here. Sometimes the better strategy is not to simply pile on more gear, but have a plan
B involving improvisation and alternatives.

I can understand redundancy when it comes to the essentials. If your backup is lite and small enough then why not carry it. Its just that a person doesn't need to have redundancy for everything or carry a lot of extra weight. DC always gets my motor running when he advocates "bomb proof" equipment. A lot of that bomb proof equipment is heavy and not practical. Some lite weight redundancy could be applied and still be lighter than his packs.

But then again, it seems like everyone out there has got some sort of slogan or catch phrase to grab people's attention or to provide a signature.

DC uses the "2 is 1, 1 is none". I've also heard "The more you know, the less you carry" and "If you're not always prepared, you're never prepared", etc.

I don't entirely agree. A knife is so critical a piece of gear that having a spare blade (like on a multi) just makes sense to me. As far as guns are concerned, I never carry more than one unless its a class, practice or competition that calls for more than one, but I imagine combat is a different story.

"When in doubt, leave it out!" is another way of putting it, at least if one is traveling by foot. I try to force myself to follow that rule. No matter how fit you are, when you carry less you can travel further and faster. Climbers have always known that carrying too much emergency bivvy gear on a day climb often insures that you will need to bivvy! You want to try to find the Goldilocks point: Not too much, not too little....just the right amount of gear!

That being said, it is sometimes worth it to carry a back up of a few really essential items. In the bottom of my pack I always have a small lightweight folding knife and some extra firemaking gear, and a few other odds and ends. In winter I always carry an extra very small headlamp. Because of the unstable and sometimes severe climate around these parts I always carry a lot more clothing than I think I will need.

On advantage of traveling lighter is that one can take other stuff just for fun. For example, in Alaska there is always the opportunity for really neat wildlife sightings. Hence I often carry a good pair of binoculars. They are a bit heavy but are just the thing when you spot a familly of bears on the next ridge over, and want to stretch out on the tundra and watch them for awhile.

Not directly related to survival items , but related to the principle itself. Yesterday my DD needed a copy of some document for the school. I am a busy guy and even a simple reuqest like that stresses my nerves , however being a prepper I relaxed and told her to wait a minute until I retrieve a copy which should be nearby.

I checked my work bag. Sure enough there were copies of several documents, but not that one. I opened the trunk and grabbed the trunk bag where I was sure to have a copy. Again, there were other copies of different stuff, but not that one. Apparently, I used up those copies earlier and did not put any more.

Yesterday, I made TEN copies and scattered them around in the work bag , trunk bag ..etc. Today, my DD isn't going to school, yet I am not saved that trip. I have to go to school just to give them the document ... It's last day to submit the document or else she won't be registered for next year.

If I had the copy yesterday, I would have saved myself big hassle.
And it is not even a survival item.

Morale of the story : TEN is one, one is none !!

Maybe that thing was just taken out it´s original context. It´s just perfect for the military. It´s simple, easy to remember as it rhymes and can be applied to different contexts. You can apply it from everything from having backup for mission critical supplies to taking care of your buddies. I´m not calling military personal silly or dumb but stress and sleep deprivation are sure to take their toll and they are not known to improve mental abilities.
For preparedness context it should be taken with liberal dose of salt. If a backup is sensible take it, otherwise let it be. If you can go to the next shop and just buy a replacement, it may not even be sensible to even own the backup.
For blades having one for rough jobs and one for fine work makes sense. With guns it´s better to have just one that´s kept perfectly clean and in good repair than having two in moderate condition.