Sorry, but there isn’t one. At least, not the deeper meaning that most people are looking for: “Why am I here? What is my purpose? What is life all about?” There’s simply no answer to those questions from the biological perspective—which as living beings is all we’ve really got. Cells don’t exist for a reason, and neither do birds, bees, sharks, dolphins, dogs, and howler monkeys. To look for and find a meaning you have to develop something beyond the body: a mind, a soul, or what you will.
Life as an expression of the making and breaking of atomic bonds—that is, millions of complex molecules coming together and breaking apart in millions of complex reactions—happens simply because it can. With the right mix of chemicals and an external energy source, you get the complex, entropy-reversing phenomenon we call life. On this planet, the covalently active atoms oxygen, hydrogen, carbon, nitrogen, sulfur, and phosphorus, operating in a flexible, supportive matrix like liquid water, supplied with massive inpourings of sunlight or geothermal steam, yield life. On other planets, other chemicals, other matrices, and other energy sources may yield a different kind of life.2
Life as we understand it consists of layer upon layer of complexity. Complex long-chain molecules called polymers, the familiar DNA and RNA, store the formulas for, and coordinate the manufacture of, even more complex polymer molecules called proteins. Proteins fold in complex ways to provide surfaces covered with the right pattern of available electrical charges to attract two or more simple molecules and force the binding reactions—protein-assisted reactions are properly called “enzymatic reactions”—that will turn them into a larger, more useful molecule. Similarly, proteins and their charge patterns can attract large molecules and break them apart, which can be just as useful in the life process.
Almost any chemical reaction can be forced with the application or the release of a sufficient amount of energy, and sometimes these are large and disruptive energies. The wonder of enzymatic reactions is that they all occur at energy levels consistent with other chemical processes going on nearby. That is, pumping in the energy to make a particular peptide bond doesn’t freeze your insides—or cook them in breaking the bond and releasing energy. Enzymes moderate the heat of reactions and let you stay at a convenient body temperature.
Complex collections of these useful resulting chemicals form the membranes and inner working parts of cells—all coordinated by their enzymatic proteins and replenished by their DNA/RNA mechanisms. Collections of cells affect the environment around them, linking together to create complex structures such as bones, muscles, blood vessels, and nerves. Groups of cells also coordinate in a complex fashion to create non-living materials such as tooth enamel, stomach acid, saliva, and tears. These materials function in the environment created by cells groups operating at a much higher layer of complexity—the body.
Within the human nervous system, the level of complexity rises many-fold. The human brain contains approximately 100 billion specialized cells called neurons, and each of these makes an average of 7,000 synaptic connections with other neurons. The resulting 100 to 500 trillion connections allow for recording, analyzing, and coordinating the body’s sensations, perceptions, and movements. From all this complex activity arises the phenomenon we call awareness and the ongoing processes of thought and memory.
These various layers of complexity take you from a collection of active chemicals in a pond to an organism capable of observing the universe, appreciating itself as a separate being, and wondering about its place and purpose in that universe. None of this complexity, however, will tell you why you exist, simply that you can.
The complexity that brings awareness won’t answer that final question. It will not tell you whether to dedicate your life to altruism, hedonism, or mysticism; follow the tenets of Buddhism, Marxism, Islam, or Dianetics; turn left or right along the political path; opt for a family or a career; enlist to fight for or against a tyrant; build a temple or a tomb.
As El Aurens says in Lawrence of Arabia: “Nothing is written.” And that’s a good thing. Our minds are assembled in complexity with sufficient innate programming that the basic mechanism functions. The optic nerve sends impulses that can be interpreted as accurate pictures of the world around us. The aural nerve carries impulses that we hear as voices or music. We can interpret meaning, call up memory, and imagine the future. But beyond that … only freedom.
If there is a God—that is, a complex, powerful mind and will, operating behind the scenes of what otherwise looks like chance, happenstance, and chaos—then He must be a subtle one. He did not create human beings out of all this complexity so that they would have ungovernable impulses that must then be governed by a set of rules you could write down in a book.3 He would not want us all forced to act in a choreographed pattern, like the linked movements of bird flocks and fish schools. That would be a universe of robots! Making programmable robots is obvious and … unsubtle.
If nothing is written, then each of us must write for ourselves. We must pick a path in life that lies within the compass of what we know, fits the span of our capabilities and interests, and remains compatible with our beliefs. But we each must recognize that beliefs can change when confronted with new views of reality. Interests will change in response to our imagination working on new opportunities. Capabilities can be acquired and improved. We start as buds in a sea of sensation and possibility. We are changed by that environment—and we change ourselves in response to it.
We can become anything we want. But we must choose carefully, because as we grow older, the path becomes steeper and the alternatives are harder to find and follow. And at the end—coming sooner than we like—we all die. We all have only so much time to identify, select, and develop the type of life that we will ultimately find satisfying and meaningful.
But still, within those strictures, “Nothing is written.”
1. You knew I’d get around to this eventually, didn’t you?
2. For example, carbon’s ability to give, take, and share up to four electrons enables it to form complex molecular structures. However, in an environment poor in carbon (atomic number 6), the element in the same position on the next row of the Periodic Table, silicon (atomic number 14), could serve the same pivotal role in a life-forming chemistry. Silicon-based life forms would be able to reproduce any chemistry that carbon-based life is capable of, but they would tend to be heavier because their constituent molecules would carry eight extra proteins and a like number of neutrons on each silicon atom.
3. If I believed in any god-as-creator, then it would be a mind that worked its actual decision-making processes far upstream of human life. It would be the mind that determined the structure of the atom and its complex electron shells that allow hydrogen, oxygen, and carbon to bind in these useful ways. That’s about as much winding up as the universe should get. After that, the power of the DNA molecule not only to record but also to mutate and change allows life to develop and the resulting creatures to evolve in response to their environment. A single creation of humankind, or any other species, in its current form would only have worked in the current conditions of temperature, oxygen concentration, water pH and salinity, meteoric bombardment rate, and a dozen other variables. Change any one variable by much, and you doom that life to extinction. To survive in a changing world, life must change. Any one species may die out—and it may have been a toss-up whether Homo sapiens or Tursiops truncatus became the dominant species on this planet (although I personally would vote for thumbs). But life persists and rolls with the punches. And because life is a complex use of common chemicals, it can exist anywhere in the universe, because the atomic structure of hydrogen, oxygen, carbon, and other elements of the Periodic Table is the same on Alpha Centauri and in the Andromeda galaxy as here.