The most significant takeaway as we approach 2021 is simply this: the Universe can be comprehended. We must not ignore the lessons it offers us.

In essence, 2020 was an unprecedented chapter in human history. For the first time in modern medical history, an airborne pathogen, which could be mitigated through straightforward public health measures, spread across all seven continents, resulting in record-breaking cases of infection and mortality. The toll we faced—from illness and death to ongoing health complications, economic fallout, and psychological distress—was largely avoidable.

It's crucial to understand that the threat was not the virus itself, but rather our failure to take responsible, coordinated action on a global scale in response to it. With vaccines gradually being distributed, many anticipate an eventual end to the pandemic as the population gains immunity. However, there's a scientific principle that should guide us through this period, one that is often overlooked.

The Universe and everything within it adhere to the same fundamental laws. Identifying and comprehending these laws, and applying them to specific phenomena, is humanity's most effective tool—arguably the only consistently effective one—for solving the challenges we face. As we leave 2020 behind and step into 2021, this understanding must be woven into the very fabric of our society.

Now, let's imagine a Universe vastly different from our own—one where the laws of nature shift unpredictably over time. Instead of gravity consistently pulling us toward Earth at 9.8 m/s², picture a reality where gravitational forces vary randomly, perhaps even reversing direction intermittently. The Sun could flicker out or burn intensely, threatening life on Earth in mere moments. The possibilities of chaos in such a Universe are endless.

Consider the atoms in your body suddenly undergoing radioactive decay, your cellular structure disassembling spontaneously, or the forces preventing our planet from collapsing into a black hole vanishing in an instant. In such a reality, predicting future events would be utterly hopeless.

When we began to explore the physical world scientifically, there was no certainty that the laws of nature would remain constant. There was no inherent reason for the rules governing our reality to be uniform across time and space. Yet, upon studying the Universe in detail—from biology to chemistry to physics, and at scales both subatomic and cosmic—we consistently find these laws to be invariant. The quantum principles that apply to atoms on Earth are the same as those governing atoms billions of light-years away.

The principles that dictate subatomic interactions, from radioactive decay to nuclear reactions, have remained unchanged for billions of years. By examining Earth's geological history, meteorites of varying ages, and even our planet's dormant natural nuclear reactor from nearly two billion years ago, we can reconstruct how stable the laws of physics have been. To the limits of our measurement capabilities, neither the governing rules of reality nor the values of fundamental constants have shown measurable changes.

Many would prefer science to provide merely facts, concluding that what we do with those facts is a collective responsibility beyond science's reach. This perspective is misguided.

If we adopt such a stance, it parallels the myth of the ostrich burying its head in the sand, willfully ignoring impending threats while failing to take action. Interestingly, that common image is itself a myth; ostriches do bury their heads in the sand, but not in response to danger. When faced with threats, they instinctively flee. If escape is impossible, they lie low, attempting to blend with their surroundings. The sight of an ostrich with its head buried arises from their nesting behavior, not from a desire to remain ignorant.

The fact that the Universe and everything in it follows the same fundamental rules is a cause for optimism. It implies that through diligent inquiry—conducting experiments, making observations, and taking careful measurements—we can uncover these rules and effectively learn the "instruction manual" for the Universe. This knowledge allows us to predict future events based on initial conditions.

The premise is straightforward: if you grasp the rules and starting conditions, you can foresee how events will unfold. While many aspects of reality complicate predictions—dependent on the models' accuracy and their alignment with reality—scientists excel at identifying which models yield successful predictions. In fields where valid objections no longer hold, an overwhelming majority of scientists (over 95%) will converge on a consensus.

Meeting scientists reveals the remarkable nature of their work. They embody professional skepticism, rigorously questioning whatever aspect of the Universe they study. While most people formulate theories or hunches, scientists delve deeper. They consider what implications their ideas hold and design experiments to test these hypotheses against observational evidence. Only after passing multiple tests within a specific range of applicability can a scientific theory gain acceptance.

The ability to understand the Universe is extraordinary, and we must be cautious not to underestimate our grasp of various phenomena. Many have attempted to instill doubt about established scientific knowledge, using tactics that exploit our instinctive distrust toward ideas that challenge our common sense or beliefs.

Sadly, common sense is often a poor predictor of scientific truths. The theory of evolution, the mechanism of natural selection, Einstein's relativity, the Big Bang theory, and germ theory—all initially countered common sense. If common sense were a reliable guide to the Universe's workings, science would be unnecessary. Our common sense, shaped by personal experience, has a narrower scope than we often realize. Learning to prioritize scientific findings over intuition is a crucial lesson for any aspiring scientist.

Occasionally, studies reveal the scientific illiteracy prevalent in the general populace. Surveys suggest that a significant portion of Americans believe the Sun revolves around the Earth, which is used to argue against their scientific understanding, as if memorizing facts equates to comprehension.

If a particle physicist were placed in a virology lab, they would struggle just as much as someone without scientific training. You wouldn't assign a polymer chemist to a nuclear reactor or a theoretical astrophysicist to surgery. While science encompasses the entirety of knowledge available at any moment and is a self-correcting process, no individual can master every scientific discipline. Instead, we rely on two often-overlooked facets of scientific literacy:

1. An understanding of what science is and how it operates.
2. An acknowledgment of how scientific advancements propel society forward.

The Universe is comprehensible. Any aspect we choose to explore with the appropriate tools and methodologies can be explained scientifically. Realizing that science is both the body of knowledge we possess and the ongoing process of inquiry should foster a deep respect for the vastness of our ignorance outside our limited expertise while simultaneously valuing the insights of specialists in specific domains.

You likely read this on a device that leverages numerous groundbreaking technologies and scientific advancements, at a point in history when humanity holds unparalleled knowledge of the Universe. Through science, we have unraveled the root causes of the challenges we face, both on Earth and beyond, and we learn how to address these issues effectively—if we choose to heed that knowledge. As Galileo famously stated:

“I do not feel obliged to believe that the same God who has endowed us with sense, reason, and intellect has intended us to forgo their use.”

As we close out 2020, it's imperative to reflect not only on the immediate challenges posed by the coronavirus but also on all facets of society where scientific guidance is overlooked. Whether it’s regarding vaccines, climate change, clean air, potable water, public health, or natural disaster warnings, science should not be treated as an a la carte menu from which we select what we find palatable while dismissing the rest.

The Universe is indifferent to our ideological beliefs, political views, or perceptions of rights and freedoms. It simply adheres to the laws of nature, and we must face the consequences of our actions—or inactions. Science serves as our beacon against the darkness of our baser instincts, yet engaging with it demands humility in acknowledging our ignorance. It’s time to integrate this understanding into our lives as individuals and into the fabric of society. Without such integration, we risk being torn apart by our own biases.

Starts With A Bang is authored by Ethan Siegel, Ph.D., writer of Beyond The Galaxy and Treknology: The Science of Star Trek from Tricorders to Warp Drive.