Originally Posted by
canid
well, i don't much like the premise, as i can't imagine any circumstance where i would have access to my preferential equipment/supplies, but somehow still be limited to one thing for each need. in addition, need changes dramatically with circumstance.
that said; here are some ideas:
fire: prepared tinder. if it's dry enough that carrying prepared tinder isn't all that helpfull, it'll be much easier to start fire in the first place. if it's too damp to reliably find it in the field; you're going to spend a lot of energy trynig to find, reach or dry it.
water: this one is a tough call. most of the things that make water procurement or treatment really handy are pretty limited, either in quantity (such as a supply of safe water itself, or a bottle of chemical treatment tablets) or quality (filter pumps can break at worst, or become quickly clogged at best, and it's faster the dirtier the water). in ether case, they don't last indefinitely, though the need for water will last the rest of your life. i am torn between two options: an initial supply of safe water itself, since some circumstances will not present an opportunity to find even unsafe water to treat, or a durable pot or kettle, which can both carry water and withstand the heat of boiling it.
food: i'm on the brinding low weight, low moisture, high caloric density foods with you bandwagon, since the available foods, and methods of procurement will be entirely dependant on circumstance. snare wire would be great, but i would not bet my life/health on it in quire the same way as i would a nice supply of summer sausage, jerky, flatbread, etc. fishing equipment is only so helpful if you find yourself in dry hills in the summer.
shelter: i like to go for versatility here. the two big items on this agenda are isolation [keeping elements such as heat robbing air movement or water, or heat elevating sun out] and insulation [keeping heat in]. there are many circumstances where only one will be necessary and there are others where you can't live or can't remain productive for long without both. in most elements i play in, isolation is the more important, and insulative materials are abundant in the field so i usually have at least a rain/wind fly. this is not much help in an extreme cold, vegetationaly barren environment.
first aid: this is a tough one. i suppose the one most likely to be life-saving in a serious injury or illness - assuming all other needs are at least minimally met - would be a broadly effective antibiotic such as doxycycline. in a more minor situation, it can be pulverized and prepared as a topical treatment for many minor wounds. in reality, the use of such an antibiotic often requires specialized knowlege and sometimes other accompanying medications. for example; it is an effective antimalarial, but on it's own it has delayed efficacy which necessitates a front line treatment first. first aid is quite complicated and there are no easy choices. sterile gauze or bandages might be the safe choice. hydrocodone is also a contender, since while it won't treat the injury or illness, it can very often mask enough symptoms to remain productive long enough to elevate your circumstances [would you want to fetch water on a compound fracture without it?]
in all; my overriding point is that there is no easy choice for most of these needs. you can't know the circumstances you'll be in before the emergency occurs, or at least not all of them. do you select the item you are most likely to find usefull, or the one most likely to save your life should the need arrive?
my conclusion is that you should only limit your preparedness for two reasons: that you can't obtian the resource in the first place or that such preparation is becoming prohibitive in itself.
