You can let a camper take all the gear they want, but I've learned that four items provide the strongest link to "civilization." Thus, the hiker who wants to be the most self-sufficient should learn how nature can provide these items: food, matches, toilet paper, and a sleeping bag. The availability of these four items provides a psychological link to our ordered, "regular" world we call civilization. Take these four things away and you can start to develop genuine survival skills.
FOOD
The art of finding food in the outdoors requires specialized knowledge of both plants and animals. Although this could take a lifetime to truly master, one can begin to reduce the amount of food brought along on outings little by little as new skills are learned.
FIRE
Making fire without matches isn't easy, but it can be done utilizing a variety of principles such as focusing or concentrating the sun's rays (magnifying glass, camera, binoculars, the lens of a flashlight, etc.), or by friction (various bow and drill devices, flint and steel, etc.), or with any of several other unique methods which might involve a firearm or flare gun, your car, or flashlight batteries. Once you learn the principles involved in any of these, it's just a matter of time and practice before you can effectively produce a fire without matches.
TOILET PAPER
Of course, it's easy to find leaves to use as toilet paper. This is primarily a psychological hurdle for many people.
NO SLEEPING BAG?
Just what are the ways in which we can go without a sleeping bag? Several hiking companions once expressed surprise when I told them that I frequently go without a sleeping bag on overnight outings. To many, the idea of no sleeping bag is incomprehensible, impossible, and miserable.
The first time I went without a sleeping bag was simply because I didn't want the bulk and weight. It was August and I was on a week-long trip in the Angeles National Forest. Although the days were hot and dry, the nights in the canyons were cold and windy. I hadn't realized how cold the nights would be when I left my bag behind. I slept in my hammock, my coat being my only cover. It was much colder than I would have preferred, but I did manage to sleep, more or less. My feet and toes were the coldest, so I wore three pairs of socks on subsequent nights that week. With the addition of a very light tarp and the extra socks, I slept well for the remainder of the week. In part, I accomplished this by allowing my body to go into a shiver whenever I began to feel cold. I'd let my body shiver for about 30 minutes, and that action resulted in enough warmth to allow me to get back to sleep.
Although my hitch-hiking days are over, I did discover many useful things during my wanderings up and down the California coast. I spent several nights sleeping in the hollow tubes in parks and playgrounds that were near the highways. These were surprisingly comfortable and dry. My brother has spent nights sleeping in hollow trees in Northern California.
A tube tent is an excellent camping companion because it's light, non-bulky, inexpensive, and you can also use it as a ground cover. I've spent many nights under the protection of a tube tent's cover, and have stayed dry even in downpours. Desiring to travel light, I simply would never carry a heavy and bulky tent, but the small tube tent works fine in most conditions.
I've also spent a night with an emergency blanket for shelter. Yes, it provides some small level of "shelter" and it does help you to retain some body heat. But, let's not kid ourselves; the emergency space blanket is a notch better than nothing and that means you'll still be very cold during the
winter.
The most common method of sleeping outdoors without a sleeping bag that I've practiced is the use of "body hollows", as taught at my Survival Training outings. These are body-sized holes, dug about three to four feet deep, and about a foot longer and wider than your body. The hollow is lined with as much soft grass and leaves that you can find. Then, once inside the hollow, you pull more material on to your body to provide even more insulation.
I've slept outdoors on many occasions like this. During all, but my first few attempts, I've slept as warm and as sound all night.
There are numerous variations on the body hollow, such as digging the hollows outward from a central fire pit so the coals keep you warm at night.
This really isn't particularly painful or difficult to do, but it is becoming a lost art since we're all so hooked on owning the latest gadgets and equipment. There's nothing wrong with having good outdoor gear. However, we lose when we decide that equipment and gadgets can take the place of personal skills, rather than just supplement personal skills.
Most outdoors folks today would be totally helpless if they were separated from their pack and sleeping bag. Yet thousands, if not millions, of aboriginal peoples in past centuries are a testament to the fact that one can survive well in the wilds with very little bedding.The lessons are there for your study and application. Just research the Indians of the America, the Masai and other tribal peoples of Africa, the Huns and other early European natives, the Australian Aborigines, and many, many others in both warm and cold climates.
John Muir would travel lightly through the Sierras and would periodically sleep up against a big rock. He build's a large fire many feet from the rock, and when the fire died down to coals, he would sleep between the coals and the rock. When the coals died down, we would put more wood on the coals.
While these methods may not be "easy" or "fun", they demonstrate that it is certainly possible to survive the night in the outdoors without a sleeping bag. It simply takes some planning, an attitude of joyous adventure and willingness to do a bit of work.