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Christwise · Discussion guide · Small group

The Contingency Argument

Why does anything exist at all, rather than nothing?

18 min lesson · advanced Does God Exist? Last reviewed April 26, 2026

How to use this guide

This guide is built for a 45-60 minute small-group conversation about "The Contingency Argument." Open with prayer, read the framing aloud, and use the questions below to surface what people actually think before you walk through the case. Aim for honest engagement over consensus.

Facilitator tips

  • Read the lesson before the meeting; you do not need to be an expert, just a guide.
  • Resist the urge to fill silence. The best discussions follow long pauses.
  • When someone raises an objection you cannot answer, write it down and follow up next week.
  • Close with a single takeaway from each member, not a doctrinal summary.

What we're studying

Even if the universe were past-eternal, a deeper question remains: why does it exist? The contingency argument targets this more fundamental issue. Leibniz's version, refined by modern philosophers, argues that contingent things require a necessary explanation grounded in a being that exists of its own nature.

The case in brief

Leibnizian form: (1) Everything that exists has an explanation of its existence, either in the necessity of its own nature or in an external cause. (2) If the universe has an explanation of its existence, that explanation is God. (3) The universe exists. (4) Therefore, the universe has an explanation of its existence (1,3). (5) Therefore, that explanation is God (2,4). The key premise is the principle of sufficient reason: there are no brute facts at the level of metaphysics. A necessarily existent being terminates the regress because its non-existence would be impossible.

What if someone says...

Common objections and responses
Objection 1

"Perhaps the universe is necessary, as Spinoza held."

Response

Spinoza's pantheism is internally coherent but extraordinarily costly: it requires that every detail of history is necessary and could not have been otherwise. Most find the contingency of particulars (the existence of this tree, this person) more obvious than any thesis that eliminates it.

Objection 2

"Why couldn't the universe itself be the necessary being?"

Response

The universe's contingency is evident in its alterability, its physics, and its dependence on initial conditions. Necessary beings have no alternative states and no parts. The universe has both.

Discussion questions

  1. Is the universe the kind of thing that could have failed to exist?
  2. Do you accept the principle of sufficient reason in everyday life?
  3. What would it mean for a being to exist "of its own nature"?
  4. [Small group] Where in your own life does this question feel most pressing?
  5. [Small group] Who do you know that wrestles with this — and how could you talk with them about it this week?

Going deeper

Primary texts and key works behind the lesson
  • Reasonable Faith
    William Lane Craig · 2008 (3rd ed.) · Natural theology
  • The Existence of God (ch. 8, Fine-Tuning)
    Richard Swinburne · 2004 · Natural theology
  • Scaling the Secular City
    J.P. Moreland · 1987 · Philosophy of religion

Notes

Space for what came up in your conversation

Christwise · christwise.org/lesson/contingency-argument · Discussion guide · Small group / Bible study

Use freely for ministry, classroom, and family contexts. Cite specific historical claims to the named scholars in the bibliography.