Theology / Hard Questions • Difficult Questions • Advanced
Natural Disasters and Physical Evil
Primary question: Do earthquakes, tsunamis, and other natural disasters constitute strong evidence against a benevolent designer, or can the very geological processes that cause them be shown to be preconditions of a habitable, life-supporting planet?
Argument map
Click any node to inspect it. Expand branches to go deeper.
Common mistakes
Don't say
Treating the 'plate tectonics is necessary for habitability' defense as a complete theodicy explaining any specific disaster.
Instead
Present it as a partial defense addressing only why tectonically active planets are broadly good candidates for hosting life, explicitly conceding it says nothing about particular events.
Don't say
Ignoring the human/social contribution to disaster death tolls (building codes, urban density, warning systems).
Instead
Acknowledge, following Rousseau's original critique, that much disaster mortality reflects a compound of natural process and human choice, which is philosophically significant.
Don't say
Dismissing Voltaire's challenge as merely literary rather than philosophically serious.
Instead
Recognize Voltaire's Lisbon poem as a landmark, rigorous philosophical challenge to theodicy that reshaped the field's terms of debate.
What would change my mind? — Christian position
Strong scientific evidence that comparable long-term habitability could be achieved without any tectonically driven seismic hazard would seriously undermine the 'necessary engine' defense and require theists to lean more heavily on natural-law or skeptical theist responses instead.
What would change my mind? — Skeptical position
A demonstration that God could institute all the described climate-regulating and life-sustaining benefits of tectonics while capping seismic events well below lethal thresholds, without incurring the costs van Inwagen describes (constant ad hoc intervention, loss of nomic regularity), would substantially strengthen the evidential argument from natural evil.
Why does this matter?
This question tests whether theodicy can move beyond citing abstract 'greater goods' to engage real geoscience, and it matters pastorally because catastrophic disasters remain among the most common triggers of genuine faith crisis, making an honest, scientifically literate, and non-triumphalist response important for both believers and skeptics evaluating the coherence of theism.
For further study
Primary and secondary sources on both sides of this question. Reading the strongest opposing case is part of the work, not a concession.
Poeme sur le desastre de Lisbonne — Voltaire
The landmark literary-philosophical challenge to providential optimism prompted by the 1755 earthquake.
Dialogues Concerning Natural Religion — David Hume
The classic philosophical treatment of design and natural evil through the voices of Philo, Cleanthes, and Demea.
The Problem of Evil — Peter van Inwagen
Develops the vagueness/threshold defense addressing natural evil within a law-governed cosmos.
Rare Earth: Why Complex Life Is Uncommon in the Universe — Peter Ward and Donald Brownlee
Establishes the scientific case connecting plate tectonics to long-term planetary habitability.
Providence and the Problem of Evil — Richard Swinburne
Develops the natural law theodicy emphasizing the value of predictable regularity for creaturely agency.
The Lisbon Earthquake of 1755 — T. D. Kendrick
A historical study clarifying the facts and legends surrounding the disaster.