When I was a Christian, one of the biggest comforts was having a well defined purpose to life. The greatest thing was to glorify God. That's easy to do on Sunday, but I figured that if God was as incredible as Christianity claimed, it was worth honoring God every day of my life. After thinking about this for a while, I decided God must care an awful lot about humanity, and seeking the advancement and peace of human civilization was the primary method of bringing God glory on a daily basis. This kind of thinking is supported by Bible texts such as "If you love me, feed my lambs", the parable of the talents, and the parable of the sheep and goats.
Psychologically, losing meaning in life was one of the three hardest parts about converting from Christianity to Atheism. However, I soon realized that removing God from the equation didn't have to change anything. I could still find meaning through the advancement of human civilization.
As a result, I've become interested in the origin and destiny of civilization. I consider a group of people to be a "civilization" when there exists a caste of the population that spends a large portion of time in activities other than the acquisition of food and reproduction. So a group of hunters living in caves wouldn't be a civilization until there is some kind of a chieftain or shaman who is supported through food from the other villagers. Civilization can't advance until people have leisure time to spend on art and science, so the beginning of civilization is when some people first have this free time.
Humans have made three major discoveries that were necessary for civilization to begin. They are language, fire, and agriculture. Language is required to share the complex, learned concepts that are the basis of civilization. Fire is required for cooking, which increases the nutritional value of food, thereby increasing the lifespan and health of the population. And farming is the most crucial of all. Through farming, a group of people can produce more food than they can consume. This both provides a buffer against years of famine and allows a segment of the population to spend time on things other than food production.
Once those three things were in place, the stage was set for the rapid advancement of technology, resulting in a far higher standard of living and population than humans had ever seen. The past 10,000 years of life on Earth have put the previous millions to shame. Of the many things humans have invented and discovered, however, I'd like to list what I consider the most important discoveries. All of these you use on a daily basis, probably without even thinking about it. They are:
Creating a writing system is not as easy as most people would think. There's an excellent discussion of why this is hard in the book Guns, Gems and Steel. The basic issue is that pictorial systems (like the Chinese alphabet) require memorizing a different symbol for each word, so learning the system difficult. And phonetic systems require a stronger understanding of phonetic units than most people have, to the extent that most people learn English spelling without even understanding the phonetic backing.
The Wheel and Roads:
These two inventions together are necessary to move large quantities of goods over long distances, and is a crucial part of trade with other cultures. Trade is the mechanism by which different cultures share their discoveries.
In trade and barter systems, it's easy for a baker who wants meat and a butcher who wants bread to work out a deal. But what happens when the butcher instead wants a knife, the blacksmith wants a table, and its the carpenter who wants bread? Now you have to orchestrate a four way trade. When you expand this problem even to a town of just 1000 people, its complexity as an NP complete problem becomes apparent. Money provides a linear time solution. Every trades what they have for money, then trades the money for what they want.
Most of the time, having directions or instructions is meaningless unless they are precise. Understanding the relationships between numbers is required for measurements, trades, and general mechanics.
Once you have even 10,000 people living in the same general area, getting fresh water and removing sewage becomes a genuine problem. Without a good system of moving water, the population is much more likely to contract and spread diseases. Sewers make cities less susceptible to plagues.
The Printing Press:
Even if you have a written language, the production of written documents is time consuming without a printing press. The press allows for mass production of books, which in turn puts written materials in the hands of the common person. That makes it the precursor of widespread education. Historically, the printing press was also one predecessor of the Protestant Reformation, as it enabled the Bible to be translated out of Latin and into a language the average person understood (at least if it were read to them).
Fire is a powerful source of energy, but it's difficult to use. Contrast this with electricity, a power source that can be transmitted over large distances and even stored for later use. Among its many uses, electricity provided more efficient means of lighting buildings. This in turn meant humans could be productive for more hours in the day. It also created more efficient climate control systems for buildings, which allowed humans to live in harsher climates. And it enabled the creation of more efficient factories using the assembly line for production.
Three thousand years ago, kings were happy that their exact instructions could be written down and sent to another place in the kingdom within a month or less. But due to the discovery of radio waves, encoded messages can be broadcast across thousands of miles in mere seconds. With radio communication, decisions require crucial information can be made in minutes rather than weeks or even months.
I am convinced that the internet is by far the greatest invention of our generation. While radio and television allowed rich corporations and governments to communicate quickly and easily, the internet has put that power in the hands of the everyone. Massive amounts of data can be send anywhere on the entire planet in a matter of seconds due to the power of the internet. It has brought about an era in which anyone with access to a computer can express their thoughts. And if Twitter is any indication, almost none of it is worth reading. But I hope that this blog can be one corner of the internet where the information is worthwhile.
When I see how far humans have come, I'm excited for the future. Some other week I'll write about some options for what The Next Big Thing(tm) might be. But given the increasingly rapid pace of technology development, it could be something we see in our lifetime. You might notice that everything on this list has to do with more efficient movement of ideas, matter, or energy, so that's a clue for what kinds of technology this next century could bring.