# Proof: Lightning never strikes the same place twice.

- **Generated**: 2026-03-28
- **Verdict**: DISPROVED
- **Audit trail**: [proof_audit.md](proof_audit.md) | [proof.py](proof.py)

## Key Findings

- The claim is a well-known myth explicitly debunked by every major meteorological authority.
- The Empire State Building alone is struck by lightning an average of 23 times per year (B1).
- Four independent authoritative sources — the National Weather Service, NOAA's National Severe Storms Laboratory, NASA, and Encyclopaedia Britannica — all confirm that lightning regularly strikes the same place multiple times (B1, B2, B3, B4).
- No scientific source was found that supports the literal claim; it exists only as a metaphorical idiom.

## Claim Interpretation

**Natural language**: "Lightning never strikes the same place twice."

**Formal interpretation**: The claim is an absolute universal negative — it asserts that no location on Earth is ever struck by lightning more than once. To disprove this, we require at least 3 independent authoritative sources confirming that lightning does, in fact, strike the same place repeatedly. This is the conservative threshold for consensus disproof; the claim is disproved if >= 3 verified sources confirm it is false.

## Evidence Summary

| ID | Fact | Verified |
|----|------|----------|
| B1 | NWS Lightning Myths page: lightning often strikes same place repeatedly | Partial (aggressive normalization, fragment match) |
| B2 | NOAA NSSL FAQ: lightning does hit the same spot more than once | Yes |
| B3 | NASA Spinoff: lightning often strikes the same place twice | Yes |
| B4 | Britannica: lightning can and will strike the same place twice | Yes |
| A1 | Verified source count confirming claim is false | Computed: 4 sources confirmed (3 fully verified, 1 partial) |

## Proof Logic

The claim "lightning never strikes the same place twice" is an absolute universal statement. A single well-documented counterexample is sufficient to disprove it, but for rigor, this proof assembles multiple independent authoritative sources.

The National Weather Service states that "lightning often strikes the same place repeatedly, especially if it's a tall, pointy, isolated object" and cites the Empire State Building being struck an average of 23 times per year (B1). NOAA's National Severe Storms Laboratory independently confirms that "lightning does hit the same spot (or almost the same spot) more than once, contrary to folk wisdom" (B2). NASA's Spinoff publication states "contrary to popular misconception, lightning often strikes the same place twice" (B3). Encyclopaedia Britannica confirms "lightning can and will strike the same place twice, whether it be during the same storm or even centuries later" (B4).

All four sources independently and unambiguously reject the claim. The verified source count of 4 meets the threshold of 3 required for consensus disproof (A1).

## Counter-Evidence Search

1. **Is there any scientific evidence supporting the claim?** Searched broadly for any defense of the saying. No scientific source supports the literal claim. Every authoritative meteorological source explicitly identifies it as a myth. Merriam-Webster defines the phrase only as a metaphorical idiom meaning "an unusual event is not likely to happen again."

2. **Could the claim be interpreted more charitably (e.g., exact microscopic point)?** Even under the most generous interpretation, the claim fails. Lightning channels are meters wide, and the NSSL confirms lightning hits "the same spot (or almost the same spot)" repeatedly. Structures like the Empire State Building are struck dozens of times per year.

3. **Are the sources truly independent?** All four sources come from different institutions with independent editorial authority. NWS and NSSL are both NOAA entities but have separate missions and publication pipelines. NASA and Britannica are fully independent organizations.

## Conclusion

**DISPROVED**. The claim "lightning never strikes the same place twice" is false. Four independent authoritative sources — the National Weather Service (B1), NOAA NSSL (B2), NASA (B3), and Encyclopaedia Britannica (B4) — all explicitly confirm that lightning regularly strikes the same location multiple times. The Empire State Building alone is struck approximately 23 times per year. No scientific source supports the literal claim.

One citation (B1, NWS) was verified via aggressive normalization (fragment match) rather than full quote match, likely due to HTML rendering differences on the .gov page. The three remaining sources (B2, B3, B4) were fully verified with exact quote matches. The disproof does not depend on B1 alone — the three fully verified sources independently exceed the threshold of 3.

---
Generated by [proof-engine](https://github.com/yaniv-golan/proof-engine) v0.10.0 on 2026-03-28.
