Skills and know-how for the survivor.

Skills - No amount of gear of even the highest quality is useful to anybody without a mind to use it. For nearly a million years humans lived with little to no tools except sticks and stones. How could they have been successful at all with such primitive and limited technology? Simple, every person was a vast repository of learned skills. Fire making, flint napping, animal tracking, animal hunting, and plant identification, even sky watching, were all common and considered basic human knowledge. Today few people can point out more than Orion's belt let alone navigate by stars. Consider that the ancient stone-age Polynesians discovered and colonized every possible island of the pacific without a compass or maps. This was done with little more than skill and knowledge. This is also where one should invest the most time and effort. Having a $100 k-bar will do you absolutely no good if you can't hunt track and dress an animal let alone build a fire to cook it... And I don't mean that everybody should know how to make an arrow head from obsidian. But I do believe that everybody should have an ability to navigate by the sky... at the very least. 

Know some numbers - having basic math skills can save your life! Knowing some measurements and how to use them can prove invaluable. The following are some numbers you should just know.

Know your body weight; body weight is a simple and basic measurement used to estimate your fitness and health. Dramatic weight loss is a very serious symptom of disease or starvation. Knowing how much your weight fluctuates will help you gauge how much food you need, use and should store. In general it is said that you can calculate your estimated daily calorie requirements by multiplying your weight in pounds by 15.

Calories in your food; for example a 17oz bottle of Olive oil has "34 servings" at 120 calories a serving this means the bottle has 4080 calories in it. This is very useful if you are on a calorie budget or rationing your food and wish to maintain a healthy weight. You don't need to memorize all the nutrition tables for everything you eat. But you should have a rough idea of how many calories most common food items have. And you should definitely have a good idea of the nutrition and caloric content of the foods to store.

Estimation of your calorie expenditure; some activities are very expensive when it comes to calories. Sitting around a fire on a warm summer night will use far fewer calories than shivering under a cold damp cliff overhang in winter. A 155 pound person walking at 4 miles an hour for 30 minutes will burn about 160 calories. That same person will burn about 220 calories by swimming for 30 minutes. These numbers all vary slightly by individual metabolism and fitness. It is said that s pound of fat has about 3500 calories or an approximation of one days worth of calories.

Carrying capacity or just how much weight can you comfortably carry? Some people, usually ill-experienced ones, hear stories of manly men who hike off into the wilds with a 60 pound back pack and think they too should or could carry a full third of their own body weight. This is simply not true. Modern advances in materials and practices have generated an industry catered to the "ultra-lite" hiker. This means minimizing your weight to exclude anything extra. Why carry a two pound cast iron Dutch oven when a two ounce titanium pot works fine. More to the point, if I'm going to carry a third of my own weight in gear I'm already on the road to twisting my ankle or at least limit my traveling to only a few miles and burn through a ton of food in the meantime. The lighter the pack, the faster the travel.

Volumes: fluid ounces, pints, table spoon/tea spoon, cups, cubic inches, and liter conversions; I personally have a hard time calculating fractions, I find it much easier to convert everything into decimals and metric units. The real reason for this is that you may not have a measuring cup handy but will probably have some sort of container of a known measurement. Being able to convert volume units into one another is a very handy thing indeed.

Meditation - See my Blog entry about Meditation as a survival skill.