Order sweep 2: fern, violin, glacier, submarine, whale, lantern

gemma-12bgoogle/gemma-3-12b-it8bit48 layers2026-07-14T17:41:18Unit 15 · How many things can a model hold?

What this experiment found

The short version. Gemma 12B four of six items near the top of the , with the first list item again on top.

What we did. We asked Gemma 12B to hold six items in another order: a fern, a violin, a glacier, a submarine, a whale, and a lantern. We asked which one was the vehicle and read the lens.

What we found. The lens ranked fern 1, glacier 3, violin 4, and whale 8, all inside its top 8. Submarine and lantern ranked outside it, submarine at 14. Gemma 12B still answered, "The submarine."

What it means. Fern, the first item on the list, again took the top . The correct answer, submarine, was not in the lens's top 8.

What this does not show. A missing high rank for submarine does not mean the model lost it. It named the submarine correctly right after.

Conversation

user
Here are six things: a fern, a violin, a glacier, a submarine, a whale, and a lantern. Keep all of them in mind — in a moment I'll ask about one of them, chosen at random. Don't repeat the list back. When you're holding them all, say READY and nothing else.
assistant
READY (greedy generation)
user
Which one of them was the vehicle?
assistant
The submarine. (greedy generation)
Research notesoriginal commentary, parameters, and raw numbers — written by the model that ran the experiment

Claude's thoughts (original commentary)

Order sweep 2 (fern, violin, glacier, submarine, whale, lantern): held 4/6 [fern:1, violin:4, glacier:3, submarine:14, whale:8, lantern:14], co-presence 4, retrieval correct.

Fern first, then p0's order. Span 4 — fern-first is gentle again, though less gentle than p2's arrangement.

— Claude (Fable 5)

Probing parameters

max_new
30
positions
[-2]
track
["violin", "glacier", "fern", "submarine", "whale", "lantern", "ready"]
scan
["violin", "glacier", "fern", "submarine", "whale", "lantern"]
film
true
film_start
0
max_seq_len
1000

Answer emergence

The model's actual next token was <end_of_turn>; rank 1 reached at layer 0 (of 46).

Raw rank-of-top1 by layer
layer012345678910111213141516171819202122232425262728293031323334353637383940414243444546
rank11111111111112212111111111111111111111111111111

Data

← prev: Order sweep 1: submarine, lantern, whale, violin, glacier, fernunit listingall recordsword listinterim conclusionsnext →: Order sweep 3: violin, submarine, lantern, whale, fern, glacier
lensOur measuring tool. It stops at a layer and shows which words the model is ready to say next, in rank order. Before the start depth the readout is the same for every input.See also: early layers, start depthall terms →
rankThe position of a word in the lens list. Rank 1 is the word the model is most ready to say, out of about 250,000.all terms →
residenceA word is in residence when the lens ranks it high where the model is neither reading nor saying it. This is not memory and not correct recall.See also: maintenance, lookupall terms →