Universal truths:
There is an article Universal Truths NATURE vol. 472 no. 7342 April 14, 2011 page 136 that pointing out that science is a search for general principles that underlie events. Well and good. Their principle interest is in the evolution of languages. Just as family trees can be constructed for living forms, so they can be constructed for languages. But just as Darwinian evolution has little to say about what a species is likely to change into next, similarly language studies are not good at predicting what change will occur in a language next.
Of course if you want a universal unifying principle, you can hardly beat the principle Marry Cousins or Die Out.
It is second only to gravity in looking at the real world. The theory of gravity is pretty good, but people were building gothic cathedrals, predicting the course of the planets and throwing at catching objects without any unifying underlying principle. We were handling gravity pretty well even though we didn’t understand it.
Try to predict earthquakes, temperatures, winds, rain, coastlines, political changes and so forth, and you will have less luck. You just get lines that wiggle. But when you look at my own graphs and the ones I have collected you will see that they are as smooth as infant skin.
And while we were doing pretty well with gravity in our lack of theory, we are really doing badly with reproduction. Most obviously at present, we have over populated the world. There have been unintended extinction events in the past and, if you want to wallow in gloom, there are numbers suggesting a global human extinction to which we will be inexorably committed during the expected lifetimes of people who are already with us.
Then there is the number of topics this affects. I doubt I can make a complete one:
Population growth rate.
History.
Religion.
Courtship. (That comes in for special mention as bewildering according to the article.)
Music.
Drama.
Art.
Clothing styles.
Cooking traditions.
War.
Prejudice.
Poverty.
You get the drift. Anything that is distinctively human. And among animals it turns out to be the bulk of natural history: what animals do and why. To a degree they are concerned with eating and not getting eaten, but there is an enormous field of courtship, quite as amazing as the human one.
So if you are looking for universal principles, you have never seen one like this.
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