A-1 - Encouraged by What You Read?

In the first two parts of this series (see here and here) I discussed how secular scientists, given their naturalistic worldview, expected to discover that we live in an eternal—and therefore uncaused—universe, as well as in an ordinary solar system. Yet on both scores scientists were surprised by what scientific advances revealed. In both cases, the great contrast for scientists who hold a purely secular worldview is that the universe’s and solar system’s features seem to best comport with the expectations of theism over atheistic naturalism.

In this article I will briefly discuss how the specific expectations of secular scientists concerning Earth’s characteristics were also very different from what science has shown. Again, the results follow a similar pattern of favoring the expectations of one worldview over another.

The Rare Earth Hypothesis

The consensus of secular scientists a half-century ago was that the earth is not a special planet, but rather a mediocre one, with no rare or unique significance. Many scientists thought that since Earth is not at the center of the universe, then it is merely ordinary. For example, in the 1970s and 1980s scientists like Carl Sagan and Frank Drake described the Earth as a typical rocky planet in a nonexceptional place in an ordinary galaxy.

However, this initial expectation has been challenged. The rare Earth hypothesis holds that the earth is distinct as a planet and may even be special. University of Washington scientists Peter D. Ward and Donald Brownlee have led the way in representing this perspective in their book Rare Earth: Why Complex Life Is Uncommon in the Universe.

They argue that the universe is fundamentally hostile to complex life and that microbial life may be common. However, the evolution of biological complexity from simple life on Earth requires an exceptionally unlikely set of circumstances; therefore, complex life is probably extremely rare.

“[A]mong the essential criteria for life are a terrestrial planet with plate tectonics and oxygen, a large moon, magnetic field, a gas giant like Jupiter for protection and an orbit in the habitable zone of the right kind of star.”1

Not all scientists accept this rare Earth view, and some have criticized the hypothesis (seehere). Yet scientists who embrace a purely naturalistic worldview expected Earth to prove to be commonplace, but instead they discovered viable reasons to think otherwise.

The rare Earth hypothesis seems to comport well with a theistic, even biblical, worldview, but appears unexpected and out of place from an atheistic, naturalistic perspective. So what would Earth look like if biblical theism were true? Evidently much like it appears right now.

In part four I’ll discuss the topic of human exceptionalism and what scientists anticipated and have discovered about it.

Reflections: Your Turn

For Christians, what does living on a planet that seems specially designed to allow for human life invoke? Visit Reflections on WordPress to comment with your response.


  • For more on Earth’s unique features, see Hugh Ross, The Creator and the Cosmos, 4th ed. (Covina, CA: RTB Press, 2018), 199–222.
  • For more on the argument to God from fine-tuning, see Kenneth Richard Samples, 7 Truths That Changed the World (Grand Rapids, MI: Baker, 2012), 113–15.

Check out more from Reasons to Believe @Reasons.org

  1. Wikipedia, s.v. “Rare Earth (book),” last modified December 8, 2018, 12:34 (UTC), https://en.wikipedia.org/wiki/Rare_Earth_(book).


About The Author

Kenneth R. Samples

I believe deeply that "all truth is God’s truth." That historic affirmation means that when we discover and grasp truth in the world and in life we move closer to its divine Author. This approach relies on the Christian idea of God’s two revelatory books - the metaphorical book of nature and the literal book of Scripture. As an RTB scholar I have a great passion to help people understand and see the truth and relevance of Christianity's truth-claims. My writings and lectures at RTB focus on showing how the great doctrinal truths of the faith (the Trinity, the Incarnation, the Atonement, creation ex nihilo, salvation by grace, etc.) are uniquely compatible with reason. This approach reflects the historic Christian apologetics statement - "faith seeking understanding." I work to help myself and others fulfill Peter's words in 2 Peter 3:18: "But grow in the grace and knowledge of our Lord and Savior Jesus Christ. To him be glory both now and forever! Amen." As an RTB scholar I have a great passion to help people understand and see the truth and relevance of Christianity's truth-claims. • Biography • Resources • Upcoming Events • Promotional Items Kenneth Richard Samples began voraciously studying Christian philosophy and theology when his thirst for purpose found relief in the Bible. He earned his undergraduate degree in philosophy and social science from Concordia University and his MA in theological studies from Talbot School of Theology. For seven years, Kenneth worked as Senior Research Consultant and Correspondence Editor at the Christian Research Institute (CRI) and regularly cohosted the popular call-in radio program, The Bible Answer Man, with Dr. Walter Martin. As a youth, Kenneth wrestled with "unsettling feelings of meaninglessness and boredom," driving him to seek answers to life's big questions. An encounter with Christian philosophy in Mere Christianity by C. S. Lewis led Kenneth to examine the New Testament and "finally believe that Jesus Christ is the divine Son of God, the Lord and Savior of the world." From then on, he pursued an intellectually satisfying faith. Today, as senior research scholar at Reasons to Believe (RTB), Kenneth uses what he's learned to help others find the answers to life's questions. He encourages believers to develop a logically defensible faith and challenges skeptics to engage Christianity at a philosophical level. He is the author of Without a Doubt and A World of Difference, and has contributed to numerous other books, including: Lights in the Sky and Little Green Men, The Cult of the Virgin, and Prophets of the Apocalypse. He has written articles for Christianity Today and The Christian Research Journal, and regularly participates in RTB's podcasts, including Straight Thinking, a podcast dedicated to encouraging Christians to utilize sound reasoning in their apologetics. He also writes for the ministry's daily blog, Today’s New Reason to Believe. An avid speaker and debater, Kenneth has appeared on numerous radio programs such as Voice America Radio, Newsmakers, The Frank Pastore Show, Stand to Reason, White Horse Inn, Talk New York, and Issues Etc., as well as participated in debates and dialogues on topics relating to Christian doctrine and apologetics. He currently lectures for the Master of Arts program in Christian Apologetics at Biola University. Kenneth also teaches adult classes at Christ Reformed Church in Southern California. Over the years Kenneth has held memberships in the American Philosophical Association, the Evangelical Philosophical Society, the Evangelical Theological Society, and the Evangelical Press Association. The son of a decorated World War II veteran, Kenneth is an enthusiastic student of American history, particularly the Civil War and WWII. His favorite Christian thinkers include Athanasius, Augustine, Pascal, and C. S. Lewis. He greatly enjoys the music of the Beatles and is a die-hard Los Angeles Lakers fan. Kenneth lives in Southern California with his wife, Joan, and their three children.

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