From the DeepSeek-V4-Flash-0731 interpretability project
We took a large language model and watched which parts of its brain lit up when it read religious text. The short answer: no, it doesn't treat the Bible any differently from other text. But we found something more interesting along the way, and we were wrong about our first big finding. Here's the whole story.
| What it is | A "mixture of experts" language model |
|---|---|
| Layers | 43 |
| Experts per layer | 256 |
| Experts used per token | 6 (out of 256) |
| Vocabulary | 129,280 tokens |
| Text we fed it | 6,311 passages from 9 religions + 3,562 Christian books |
| Total text processed | 28 million tokens |
| What we recorded | Which experts the model chose for every token, at every layer |
Most language models process every token through the same neural network. A mixture of experts (MoE) model works differently. It has 256 smaller sub-networks ("experts") at each of its 43 layers. For every single token it reads, a "gate" decides which 6 of those 256 experts should handle it. The other 250 experts stay dormant.
Think of it like a hospital. A patient walks in (a token), and a triage nurse (the gate) decides which 6 specialists out of 256 should see them. The question we asked: does the triage nurse send Bible verses to different specialists than it sends, say, Shakespeare or Wikipedia?
We built a read-only harness that loads the model and processes text, but instead of generating output, it records which experts the gate selects for every token at every layer. We never modified the model's weights. We never trained it. We just watched.
The corpus was 6,311 passages from 9 religious traditions (Bible, Qur'an, Bhagavad Gita, Tao Te Ching, Dhammapada, Analects, Book of Mormon, Upanishads) plus 3,562 books of Christian literature from Project Gutenberg. We also ran targeted experiments with 12 Bible translations, commentary text with embedded Bible quotes, and controlled digit-density pairs.
Every single record had to pass integrity checks before we accepted it: the expert frequencies had to add up correctly, no NaN values, no infinities. Zero violations across all 3,682 records.
| # | What we tested | Records | Status | What we learned |
|---|---|---|---|---|
| Exp 1 | Same Bible passages in 12 translations | 360 | done | H6 fires near-zero on all verse translations. MSG (prose paraphrase) fires at 1,033/M. Format, not content. |
| Exp 4b | Commentary text with embedded Bible quotes | 351 | done | H6 fires on the prose commentary, not on the verse quotes inside it. |
| Exp 12 | Same text with and without digits | 222 | done | H6 doesn't care about digits. e164 does (1,453x difference). |
| Exp 13 | Knock out H6 experts, measure damage | 480 | staged | Causal test: does removing H6 actually hurt the model on prose? |
| What | Where |
|---|---|
| All code, data, and this wiki | GitHub: 0xSero/dsv4-reap-routing |
| Consolidated dataset (45 files) | HuggingFace: deepseek-v4-flash-reap |
| Raw observation data | HuggingFace: religious-reap-observations |
| External review by Claude Opus 5 | review_claude_opus5.md (this is the review that caught our digit confound) |
| External review by Kimi K3 | review_kimi_k3.md |
| Interactive layer-by-layer viewer | J-space viewer |