Although it is difficult to define life--partly because animate objects are diverse and partly because inanimate objects are sometimes lifelike--one can describe some characteristics of living things that nonliving things do not share. Two such qualities are the ability to respond to stimuli and the capacity to evolve.
Organisms detect and respond to external and internal stimuli from their environments. Animals have complex sensory organs and muscular systems that allow them to perceive and react to light, sound, chemicals and other stimuli from their surroundings. Furthermore, receptors in their brains perceive internal stimuli. For example, when I feel hungry, I am perceiving contractions of my empty stomach and low levels of sugars and fats in my blood. I react to external stimuli by choosing an appropriate object to eat, such as a piece of blackberry pie rather than a ceramic plate.
Animals, with their elaborate nervous systems and motile bodies, are not the only organisms to detect and respond to stimuli. The plant in my kitchen grows toward a window, and the bacteria in my intestine manufacture different digestive enzymes, depending on whether I eat a piece of pie, drink a glass of milk, or do both.
If one argues that a stimulus is something that evokes a response, then the basis of the relationship between stimulus and organism is communication. Minimally, communication requires a sender, a medium, and a receiver. With respect to the plant in my kitchen, the sender is our sun, the medium is light, and the receiver is my plant, Fetus. Internally the sender is a leaf, the medium is mesophyll, and the receiver is the leaf's chloroplasts. We can continue to the subatomic level, but let us conclude with the fact that, biologically, communication is the transmission of information from one organism to another.
If nonverbal and verbal communication is the foundation of life, then without it species would become extinct. Although the genetic makeup of a single organism remains the same in its lifetime, the genetic composition of a species as a whole changes over many lifetimes. Mutations and variable offspring (Reproduction requires communication.) provide diversity in the genetic material of a species. In other words, the species evolves.
The evolutionary process has led to our ability to question reality, which separates us from other species. Furthermore, societies have been evolving because humans have been addressing such fundamental questions as: who are we, and why are we here? The answers to those two questions are complex, and they vary from one society to another. Simply, the answers help create a national or communal identity. On an individual level (Who am I, and why am I here?), the answers help create a personal identity, a reason to live in a society. For example, I am Stephen Anderson Tulloh, and I am a writer and an educator.
Creative people, such as writers, and critical people, such as educators, develop their minds via continual questioning. It is important that you realize the extraordinary power of questions--who, what, when, where, why and how--their ability to elicit ideas and information. Certainly people will disagree with your answers, for they have their own ideas and information. Thus, you must logically, emotionally and ethically persuade them that your answers are worthy of careful consideration.
People walk and talk persuasively as much as they breathe. All language--nonverbal and verbal, objective and symbolic--is persuasive, points in a direction and asks for a response. From a nod to this morning's news, from the Blue Ridge Mountains to the American flag: texts everywhere beg for responses. Everything is an argument. Read me, texts claim. To persuade, to argue is as natural and everyday as breathing. It is something we do from the moment we are born; an infant's initial cry is a claim: I have arrived!
