Every age shares characteristic foundational concepts which can seem barely credible to descendants after a few hundred years. Shared definitions make complex language possible. Most humans hold these assumptions unconsciously. If you never think about it, chances are that's a hidden assumption.
So what is true and what is arbitrary? The older I get, the more things I once assumed to be true turn out to be false, arbitrary or merely fashionable. Stuff everyone knows is usually wrong. My list follows:
1. Soap. You don't need soap in the shower. All the stink and dirt just washes off. Your skin will be healthier because it is not attacked by soap every day. The routine use of soap only enriches the soap maker. You have to rub the dead skin cells away, like with a washcloth or some rough bark, or you might get pimples like an over-oily kid.
2. Deodorant. Your pits smell bad because bacteria have had some hours to generate compounds that offend noses. Wash more often. You will not stink for hours.
3. Oily or greasy contamination requires soap and water to remove. Olive oil works just as well and is actually good for your skin. If there is not enough water to wash, oiling up and then wiping or scraping off the oil, the practice in classic Rome, works very well. Oiled skin both feels and looks good.
4. Being fat is unhealthy. No, consistently eating more food than your body needs is bad for you. Fat will see you through famine. Being fat and sedentary will kill you.
5. Never walk if you can ride. Your body walks any distance superbly. If you stop walking, you lose the ability to walk. A healthy body moves.
6. Food beyond the expiration date is unhealthy. Your eyes, nose and taste will warn you if something is unhealthy to eat with one exception. Improperly preserved food can contain undetectable botulism toxin.
7. People need three meals a day. If you do not do physically demanding work, three meals a day will make you fat. Healthy adults can handle seasons of no food quite well. The old, sickly and very young may die after some weeks. Fasting is quite safe. Famine is normal. Continuous plenty is abnormal.
8. Some people are failures. No, some people give up. How long did it take gravity to teach you how to walk? Nothing ever works the first time or even the first hundred times.
9. Miracles happen. No, miracles originate as fraud or false perception. We use metal machines to transport ourselves through the air. They function reliably no matter what we think of science or how many scientific "theories" we deny. Boarding an airliner is to deny miracles, to deny exceptions to scientific theories. If God could make exceptions to natural laws, then airplanes would sometimes inexplicably fall out of the sky. We live with dangerous machines that never kill us. With a scientific education, people can design things that function in a predictable manner until they break or wear out. With a religious education you can not make machines but you can control people.
10. You catch colds from being cold. No, if you do not get enough sleep your immune system cannot fight off disease. People have routinely lived in cold places without much clothing. We live very pampered lives.
11. Bathe or shower every day. As a kid I watched my grandfather "wash up" first thing in the morning and then before dinner. You can stay clean enough for women with a washcloth and a quart of hot water before meals.
12. Modern is better. No, modern stuff has been designed with so little wear margin that it breaks after a few years and must be regularly repurchased. I will die years from now with my 1990 Maytag washer and Gas dryer. It was almost the last generation of appliances designed to be repaired. Every five or ten years I have to fix something. How long have you had this particular cell phone?
13. Technology advances. No. It oscillates from good to bad, back and forth. We get more, then we get less more quickly. Back and forth. I grew up with inexpensive black and white film cameras. Color was available but not practical in very low volumes. My first camera made roughly two by three inch contact prints after the drug store sent them out for processing. In high school I learned to use larger format cameras and how to make 8 by 10 inch enlargements. Then Polaroid cameras became popular. At first, they made tiny black and white positive images in a minute. Much poorer quality than my childhood Brownie camera.
When SX-70 color Polaroid cameras came out I bought the original model, convinced it would be a timeless classic. I do not have many pictures from those days because the camera was not particularly good in very many situations. Then one day film was no longer sold and the camera was useless.
I remember seeing a black and white video on a Macintosh computer. Only an inch square, I was not impressed. In the 1990s cellular phones became small and very good. The sound was spectacular with digital. You could literally hear a pin drop, as Sprint advertised. Then phones got teeny cameras. They were very popular but the pictures were so small I considered them a joke. You could only get them out of the phone through the phone company.
I worked very hard in the late 1990s to take good color photos on 35 mm film. I bought a film scanner to get the photos into my computer. Then, around the millennium affordable 4k cameras arrived that produced images as good as 35mm film, but not much better. I went digital.
Passable to good, good to really good, then back to tiny barely passable pictures again. Forward to good color instant photos, then crappy tiny digital photos.
