1.1 Consider the stick.
Without a doubt, shortly after the first early human picked up a stick, the value of leveraging, nudging or hitting has been appreciated. In the hands of a sentient being, most advantageously one with an opposable thumb, a stick or tree branch can be brought down on the skull of an animal or foe to provide food or protection. A sharp stick is just one jab away from being a spear. It can be used to poke and prod campfires and dig for roots or burrowing animals. Not all uses of a stick are in the realm of hunting or combat.
With the barest minimum of manipulation, the end of a stick can be wedged under a heavy object. With upward force on the other end of the stick, the object may be moved. By bringing the middle part of the stick down on a fulcrum, further downward motion may be used to raise the object.
A stick contains in its structure the means for which mechanical advantage of leverage may be taken. What is missing is only the motivation to do so.
1.2 Tools
The advance of human civilization is substantially the story of mankind’s ability to master the material world around them. The development of agriculture and the domestication of animals allowed for permanent settlements and away from the nomadic life. The development of settlements led to the beginning of specialty occupations by people and food surplus. Food surplus allowed for time and resources for specialists to develop tools to increase labor efficiency.
Many tools have the elements of simple machines[1]. Simple machines are devices used singly or in combination to turn one kind of motion into another. For example, a screw converts rotational motion into translational motion. A wedge turns translational motion into diverging motion on an object as with the splitting of wood. A shovel uses the spade of the shovel as a wedge and the handle as a lever to raise soil from the ground. Likewise with an adze or hoe.
More important than motion conversion is the matter of mechanical advantage. Force can be amplified by the use of one or more machine elements.
In the world of bulk matter, material objects are subject to alteration by nature or by human engineering. Rock at the surface of the earth is prone to chemical weathering and mechanical attrition by the forces of nature. In the hands of engineers, rock may be fractured, cut, or milled into desired shapes. Some kinds of rock are easier to work than others. Limestone or sandstone, by virtue of their cementitious nature, is easier to hammer or chisel into desirable shapes than many harder igneous or metamorphic forms of rock.
Throughout recorded history and by observation of archeological evidence dated well before recorded history began, humans have been exploiting material objects around them. This advantage taken of materials has involved physical and chemical alteration.
1.3 Energy
Living organisms have been external exploiting energy from the very beginning of life. The second-by-second machination of life requires that molecular mechanisms be in place to assemble or disassemble molecules. This is done by making and breaking chemical bonds. Forming a chemical bond- the arrangement of charges by which molecules are held together- commonly releases energy into the surroundings. This is called exothermicity. The opposite process, breaking a chemical bond, commonly absorbs energy from the surrounding environment. This is called endothermicity.
Mankind has been exploiting energy from the earliest times simply by eating food and using the derived energy to hunt, gather, farm, reproduce, and make fire. Food energy is capable of some very dramatic things. Before steam power, food energy used by animals or humans along with the clever use of elementary machines built the pyramids of Egypt and Meso-America. Food energy powered the construction of Stonehenge, the Great Wall of China, Rome and architecture all over the world.
Food energy had its limits, however. For humans, food energy could not light up the darkness of night, make steam, smelt iron or calcine clay into pottery.
Fire is an energy releasing phenomenon that has long been exploited by nature in the form of forest and prairie fires. Although initially highly destructive, fires are useful for the rapid recycling of life giving minerals back to the soil. The loss of prairie grass or forest canopy by fire provides opportunity for new and diverse species to invade and thrive.
Fire in the hands of early human beings allowed them to stay warm and see in the dark of night. Fire allowed early humans to handle and direct a large magnitude of concentrated energy. But unlike the kinetic energy of a swinging hammer or a sharp axe, fire gave man thermal energy. Thermal or heat energy from fire was fundamentally different in its utility to mankind.
A knife or a hammer could cut or smash matter and a lever could move it. A sharp axe could fell a tree or an enemy. But fire, like the metabolism of food, could change the fundamental nature of materials. Fire gave mankind the ability to advance from altering the shape or size of a material to changing its composition. Foods could be made more palatable by cooking. Clay could be fired to yield stronger and more durable objects. Eventually, humans would discover that fire could be used to reduce metal ores to purified metal. From the hearths of industrious people came the bronze and iron ages.
On the darker side villages could be burnt to the ground and witches could be dispatched by burning at the stake. Bronze and iron would find use in armaments. With benefits come inevitable hazards.
1.4 Mechanization
One particular metric of mankind’s progress over the millennia has been the mechanization of our use of tools. Tools of the past were made of stone, wood or metal and were operated by the input of muscle energy. Tools are contrivances that enhance the user’s ability to apply force to objects in order to do something useful. A rock can be lifted to store potential energy and then be brought down on a prey animal for a kinetic kill or to expose the brain or bone marrow for rich nutrients. The bow or atlatl was used to accelerate flesh penetrating kinetic energy weapons in hunting or in battle. Some early weapons allowed for the storage of potential energy for release at the command of the user. The bow or catapult are examples of devices that allowed for the accumulation and short term storage of potential energy.
Over time, the screw, the lever & fulcrum, the pulley, numerous gearing mechanisms, the water wheel, the wagon wheel, springs, grinding wheels, and other devices were developed to store or aid in the application of force to a work piece or material.
Until the invention of gunpowder, the application of energy was largely in the form of fire or through the agency of an axe, bow, hammer or spear. Fire could be used to heat, melt, calcine, or cook materials in a reliable way. Fire was a phenomenon that could be used to apply intense thermal energy to objects. Fire was an early chemical tool.
The advance of technology is often the concentration or intensification of force. The spear or the arrow are tools that concentrate force by providing a cutting edge with a relatively small surface area.
1.5 AI
The invention of the transistor has evolved to into complex semiconductor devices converting computers from mere word processing engines to devices that can simulate human analysis and cognition. Presently, we are only part way through this step change. Just like the invention of the bow and arrow, the spear and gunpowder allows humans to apply lethal force at a distance, what will artificially intelligent (AI) machines allow us to do from a safe distance? Within 50 years or so of the discovery of compositions capable of deflagration i.e., what we now call gunpowder, it was weaponized for the purposes of war. We see the latest step change now with autonomous “smart” weapons like drones and robots in the Putin-Ukraine war. Can we resist the temptation to use AI not for more efficient inhumanity but for the betterment of mankind? I wish I could be more positive, but restraint seems unlikely.
[1] Simple machines have been listed as the lever, wheel and axel, pulley, inclined plane, wedge, and the screw.
