The Magic of Reality

1. Reality is everything that exists, and science helps us understand it

Reality is everything that exists. That sounds straightforward, doesn't it? Actually, it isn't. There are various problems.

Science reveals reality. While our senses provide direct evidence of many things that exist, science allows us to detect and understand aspects of reality beyond our immediate perception. Through instruments like telescopes and microscopes, we can observe distant galaxies and tiny microorganisms. Scientific models and theories help explain phenomena we can't directly see, like atoms and evolution.

Testing ideas is crucial. The scientific method involves proposing models to explain observations, then rigorously testing those models through experiments and predictions. This process has revealed far more about the nature of reality than myths or supernatural explanations. Science remains open to new evidence and revises theories when needed, gradually building a more accurate understanding of the universe.

2. There was no "first person" - evolution is a gradual process

Every creature ever born belonged to the same species as its parents (with perhaps a very small number of exceptions, which I shall ignore here).

Evolution happens gradually. There was never a sudden jump from one species to a new one. Instead, populations slowly accumulate small changes over many generations. If we could trace our lineage back millions of years, we'd see a gradual transition from modern humans to earlier hominids to primate ancestors.

Ancestry is a continuum. While we categorize species as distinct groups, the reality is a continuous chain of ancestors and descendants. Each individual is only slightly different from its parents, but over millions of years these small differences add up to major changes. This explains how complex organisms evolved from simpler forms of life over billions of years.

• No clear dividing line between species in evolutionary history
• Gradual accumulation of changes over many generations
• Continuous chain of ancestry links all life

3. The diversity of life is explained by natural selection and isolation

Natural selection nudges evolution in a purposeful direction: namely, the direction of survival. The genes that survive in a gene pool are the genes that are good at surviving.

Natural selection drives adaptation. Organisms with traits that help them survive and reproduce in their environment are more likely to pass those traits to offspring. Over time, this leads populations to become better adapted to their habitats. Genetic variations that are harmful tend to be eliminated, while beneficial mutations spread.

Isolation leads to diversity. When populations become separated by geographic barriers like oceans or mountain ranges, they evolve independently. This allows them to adapt to different environments and eventually become distinct species. The diversity of life on Earth is largely explained by this process of populations becoming isolated and evolving separately over millions of years.

• Beneficial traits become more common in populations over time
• Harmful variations tend to be eliminated
• Geographic isolation allows independent evolution of populations
• Separated populations adapt to different environments

4. Matter is made of atoms, which are mostly empty space

Even the legendarily hard diamond is almost entirely empty space!

Atoms are mostly empty. While solid objects feel and appear solid to us, at the atomic level they consist primarily of empty space. The nuclei of atoms, which contain most of their mass, are tiny compared to the overall size of atoms. The vast spaces between nuclei are occupied by electrons, but these are so small that atoms are still mostly empty.

Forces create solidity. The reason solid objects feel solid, despite being mostly empty space, is the electromagnetic forces between atoms. These forces prevent the atoms in your hand from passing through the atoms of a table, for instance. Understanding the structure of atoms and the forces between them helps explain many properties of matter.

• Nuclei are tiny compared to overall atom size
• Electrons occupy very little space
• Electromagnetic forces prevent atoms from passing through each other
• Understanding atomic structure explains material properties

5. Earth's rotation and orbit cause day, night, and seasons

The illusion that the sun moves across the sky is just that – an illusion. It's the illusion of relative movement.

Earth's rotation causes day and night. The planet spins on its axis, completing one rotation every 24 hours. This creates the illusion of the sun moving across the sky, when in fact it's the Earth that's moving. One side of the planet faces the sun (day) while the other faces away (night) as we spin.

Earth's tilted axis causes seasons. The planet's axis is tilted about 23.5 degrees relative to its orbit around the sun. This means that during part of the year, the Northern Hemisphere is tilted towards the sun (summer) while the Southern Hemisphere tilts away (winter). Six months later, the situation is reversed. The tilt affects both the length of days and the angle at which sunlight hits the Earth's surface, creating seasonal changes.

• Earth rotates once per 24 hours
• Rotation creates day/night cycle
• 23.5 degree axial tilt
• Tilt causes seasons as Earth orbits the sun

6. The sun is a star powered by nuclear fusion

The sun is a star. It's no different from lots of other stars, except that we happen to be near it so it looks much bigger and brighter than the others.

Nuclear fusion powers the sun. Deep in the sun's core, tremendous pressure and heat cause hydrogen atoms to fuse into helium. This nuclear fusion releases enormous amounts of energy, which eventually reaches us as sunlight. The sun has been fusing hydrogen for about 4.6 billion years and will continue to do so for several billion more years.

The sun is an average star. While it appears uniquely bright and large to us, the sun is actually a fairly typical star in terms of size and brightness. There are many stars much larger and brighter, as well as many smaller and dimmer. Our sun only appears special because of its proximity to Earth. Understanding the sun helps us understand stars throughout the universe.

• Hydrogen fuses into helium in the sun's core
• Fusion releases energy that becomes sunlight
• Sun is 4.6 billion years old
• Many stars are larger/smaller or brighter/dimmer than our sun

7. Rainbows reveal the spectrum of light

Newton discovered that white light is really a mixture of all the different colours.

White light contains all colors. When white light passes through a prism or water droplets, it separates into the visible spectrum of colors we see in a rainbow. This demonstrates that white light is actually a combination of all colors of visible light. Understanding the nature of light as a spectrum helps explain many optical phenomena.

Rainbows form through refraction and reflection. Sunlight enters water droplets in the air, bends (refracts) as it slows down, reflects off the back of the droplet, and separates into colors as it exits. Different wavelengths of light bend at slightly different angles, spreading out the colors. This process happening in millions of droplets creates the arc of a rainbow. The specific angle required to see a rainbow explains why they appear to move as you do.

• White light separates into spectrum of colors
• Refraction occurs as light enters/exits water droplets
• Internal reflection in droplets
• Millions of droplets create rainbow effect

8. The universe began with the Big Bang about 14 billion years ago

According to the modern version of the big bang model, the entire observable universe exploded into existence between 13 and 14 billion years ago.

Evidence supports the Big Bang. Observations of distant galaxies show they are moving away from us, and the further away they are, the faster they're moving. This suggests the universe is expanding. Working backwards, scientists calculated that the expansion began about 13.8 billion years ago with the Big Bang. Other evidence, like the cosmic microwave background radiation, further supports this model.

The early universe was very different. In its earliest moments, the universe was incredibly hot and dense. As it expanded and cooled, it allowed the formation of subatomic particles, then atoms, then stars and galaxies. Understanding the Big Bang and early universe helps explain the large-scale structure of the cosmos we observe today.

• Expanding universe suggests a beginning point
• Cosmic microwave background is "afterglow" of Big Bang
• Universe cooled and expanded over billions of years
• Formation of particles, atoms, stars, and galaxies followed

9. Life on other planets is possible but unproven

Nobody knows. If you forced me to give an opinion one way or the other, I'd say yes, and probably on millions of planets. But who cares about an opinion? There is no direct evidence.

Many planets likely exist. Astronomers have discovered thousands of planets orbiting other stars, suggesting planets are common in the universe. Given the vast number of stars, it's likely there are billions of planets in our galaxy alone. Some of these may have conditions suitable for life as we know it.

Life's requirements are uncertain. While we know life on Earth requires liquid water, we can't be sure all life would have the same needs. The sheer number of planets means that even if life is rare, it could still exist elsewhere. However, we currently have no direct evidence of life beyond Earth. The search continues through methods like analyzing the atmospheres of distant planets for signs of life.

• Thousands of exoplanets discovered
• Billions of planets likely in our galaxy
• Some planets may have Earth-like conditions
• No direct evidence of extraterrestrial life yet

10. Earthquakes are caused by tectonic plate movements

An earthquake is what we feel when one of those jerks happens.

Earth's crust is divided into plates. The surface of the Earth consists of large, slowly moving tectonic plates. These plates carry the continents and ocean floors, moving a few centimeters per year. The theory of plate tectonics explains many geological phenomena, including the formation of mountains and ocean trenches.

Plate movements cause earthquakes. As plates move, they sometimes get stuck against each other due to friction. Stress builds up over time until it suddenly releases, causing the ground to shake. This explains why earthquakes tend to occur in specific regions along plate boundaries. Understanding plate tectonics helps predict where earthquakes are likely to occur, though precise timing remains difficult.

• Earth's crust divided into large plates
• Plates move a few cm per year
• Friction between plates causes stress buildup
• Sudden stress release causes earthquakes

11. Bad things happen due to natural causes, not divine punishment

The universe has no mind, no feelings and no personality, so it doesn't do things in order to either hurt or please you. Bad things happen because things happen.

Natural causes explain misfortune. Disasters, diseases, and other negative events occur due to natural processes, not as punishment or reward from supernatural forces. Earthquakes result from plate tectonics, diseases from pathogens or genetic factors, and accidents from random chance or human error. Understanding the true causes of misfortune allows us to better prevent or mitigate their effects.

Perception biases affect our thinking. Humans tend to see patterns and intentionality where none exist. We remember and discuss unusual coincidences while ignoring the countless non-coincidences. This can lead to superstitious thinking or beliefs in fate and divine intervention. Recognizing these biases helps us interpret events more rationally and avoid false explanations for why things happen.

• Natural processes cause disasters and diseases
• Random chance plays a role in many events
• Humans tend to see patterns in randomness
• Understanding true causes allows better prevention/mitigation

12. Miracles are better explained by science than supernatural claims

Usually when we hear a miracle story it's not from an eye witness, but from somebody who heard about it from somebody else, who heard it from somebody else, who heard it from somebody else's wife's friend's cousin … and any story, passed on by enough people, gets garbled.

Miracle claims lack evidence. Reports of miracles are often based on hearsay, exaggeration, or misunderstanding of natural phenomena. As stories are retold, details tend to change and become more dramatic. When investigated, most miracle claims have natural explanations or insufficient evidence to support supernatural causes.

Science provides better explanations. Many events once considered miraculous are now well understood through scientific investigation. For example, diseases once thought to be caused by spirits or divine punishment are now known to be caused by microorganisms or genetic factors. As our scientific understanding grows, the need for supernatural explanations diminishes. Embracing scientific explanations allows us to better understand and interact with the real worl

Last updated: August 13, 2024