Adapting to a new world and reasoning correctly about which outcomes are possible under rules one has not met before is a basic capacity underlying general intelligence. We study it in small discrete worlds: sets of grid configurations consistent with a shared set of rules, concretely Sudoku-like puzzles built from a common base and a handful of extra rules. We train a single depth-recurrent model on many combinations of rules and test it at four levels of novelty: a new puzzle, a new combination of known rules, a pairing of rules never seen together, and a rule instance not seen at all during training. The model receives the active rules either as a symbolic description or as two solved examples, and a model that gets no rule information is used as a baseline. At recombining rules it was trained on, the description matches or exceeds examples (99% against 95% on new combinations). On rule instances whose components never co-occurred in training, the description falls below the no-information baseline while examples stay above it. The framework allows us to test many such generalization regimes in more systematic way than benchmarks such as ARC-AGI and provides new ground for evaluating depth-recurrent reasoning models, which are typically tested on saturated Sudoku benchmarks.
Figures & tables
Figure 1: A completion problem (Definition 2.3 ): given cells D (left) determine a unique admissible configuration x (right) in some world WN(A,F) . This particular puzzle comes from the concrete family introduced in Section 3 .
Type
#
Description of the rules of this type in the family
Unique-occurrence regions - a region where each symbol appears at most once
11
A fixed support (a 2×3 box, its scattered counterpart, a diagonal, a window, the four center or corner cells) contains each symbol at most once.
Adjacency - cells in a fixed spatial relation must differ
2
Two cells a knight’s move apart ( AntiKnight ) or diagonally adjacent ( AntiKing ) never share a value.
odd
Value-restricted regions - a region confined to a fixed subset of values
4
Every cell of a diagonal takes values in a fixed set V⊆{1,…,6} (odd or even).
+k
Value-shift relations - two regions whose values are related by a fixed offset
32
A pair of rows or columns a,b (one specific pair, or all three pairs of the top and bottom halves) satisfies b=a+kmod6 cell by cell, k∈{1,…,5} .
Table 1: Rule types in the 49 -instance pool V . Every rule is a set of forbidden patterns on the 6×6 grid; the glyph shades the cells one instance of the type constrains. Full per-instance definitions in Appendix A .
Setup
Prefix
Len.
Symbols used
What the model must do
no-information
none
36
7
Infer the rules from the given cells alone; lower bound on how much rule information the puzzle itself carries.
description-based
4 rules ×4 tokens
52
36
Read the rule identity as symbols and apply it.
example-based
2 solved grids ( 72 tokens)
108
7
Infer the rules from the examples, then apply them; mirrors the ARC-AGI format.
Table 2: The three conditioning setups. Only the prefix placed before the 36 puzzle cells differs.
Figure 2: Overview of the setup. (a) Example world: list of rules and schematic representation of these rules. (b) How the rules are communicated: information is appended before the puzzle under diverse forms. (c) Illustration of the forms of novelty. Letters designate rules.
mixed split
no-mix, draw 1
L3 dial split
Setup
L0
L1
L2
L3 unsupported
L3 supported
no-information
60.5±0.8
65.4±1.6
63.1±1.8
52.1±2.3
56.7
description-based
99.2±0.1
98.5±0.2
67.6±5.5
34.6±6.4
79.0±5.4
example-based
95.2±1.2
95.4±1.1
82.3±1.6
65.0±0.8
90.8±2.3
Table 3: Exact-match accuracy in percent, mean ± standard deviation over 4 training seeds, for the three setups at the four novelty levels. L1 is measured on the mixed split and L0 on the held-out puzzles of the validation worlds. L2 is measured on draw 1 of the no-mix split, on worlds containing cross-group pairs. Both L3 columns use the L3 dial split with the same held-out instances and test worlds: unsupported at level 0 (no supporting instance in training), supported at the natural exposure level ( 228 supporting worlds). Best value per column in bold.
Setting
description-based
+ dropout
floor
example-based
L3 dial, level 0 (unsupported)
34.6±6.4
58.8±1.6
52.1±2.3
65.0±0.8
no-mix split, L2
67.6±5.5
71.8±2.2
63.1±1.8
82.3±1.6
no-mix split, L3
58.7±3.2
66.6±2.1
61.7±1.6
77.0±2.2
L3 dial, level 0, L1 (in support)
98.3±0.9
96.5±0.2
75.4±0.9
98.0±0.1
Table 4: Description dropout. Exact match in percent, mean ± standard deviation over 4 seeds, evaluated with the description present; floor is the no-information model on the same split. The last row shows the cost on in-support rules. Full results, including further splits and evaluation with the description masked, in Appendix C.3 .
Appendix figures & tables20 assets
Supplementary material from the paper’s appendix.
Appendix
Figure 3: Left: the BoxesRect2x3 rule requires the six cells physically inside one 2×3 box (shaded, one possible filling shown) to together contain every symbol exactly once. Right: its scattered counterpart ScatteredRect2x3 instead groups the six cells that share the same position across the grid’s six boxes (here, each box’s top-left corner, shaded) into one such group.
Figure 4: Left: MainDiagonal requires the six cells on the ↘ diagonal (shaded, one possible filling shown) to together contain every symbol exactly once. Right: AntiDiagonal imposes the same requirement on the six cells of the ↙ diagonal instead.
Figure 5: Left: AntiKnight forbids the highlighted cell (dark grey) from sharing a value with any cell a chess knight’s-move away (red). Right: AntiKing forbids the same cell from sharing a value with any diagonally-adjacent cell (red).
Figure 6: Left: ParityDiagOdd restricts every cell on the main diagonal (shaded) to the odd values {1,3,5} ; unlike the earlier diagonal rule, repeats are allowed here, since membership in this fixed set is all that is required. Right: ParityADiagEven applies the analogous restriction to the anti-diagonal, with the even set {2,4,6} . The remaining two combinations, ParityDiagEven and ParityADiagOdd , swap which parity set applies to which diagonal.
Figure 7: The three window placements (shaded, one possible filling shown), with the 2×3 box tiling from Figure 3 overlaid as a dashed reference grid. Windows6 ’s pair straddles the box boundaries, in the spirit of a real Windoku puzzle. WindowsWrapH and WindowsWrapV instead each wrap a window pair around the grid’s border (matching shade intensity marks the two pieces of the same window, split across the wrap); neither ever coincides with a BoxesRect2x3 box.
Figure 8: Both rules cut the grid into two fixed areas and then shift the alphabet value , position by position, by k between them - the areas themselves never move or depend on k ( x′ denotes x shifted by k in the alphabet, mod 6 ). Left: RowShiftK{k} cuts the grid into a top and a bottom area (one column shown: top values a,b,c ; the corresponding bottom values must be a′,b′,c′ ); every other column is cut and shifted the same way. Right: ColShiftK{k} is the column-wise analogue, cutting a left and a right area instead.
Figure 9: Left: RowLink{0,5,k} links only row 1 and row 6 (shaded) - every column’s value in row 6 must equal its value in row 1 shifted by k in the alphabet ( x′ denotes x+kmod6 ); every other row is unconstrained by this rule. V includes two more such row pairs, (2,5) and (3,4) (1-indexed), and the column analogues, each at any k∈{1,…,5} as a separate instance. Right: ColLink{0,5,k} is the column-wise version, linking only column 1 and column 6 .
Figure 10: Left: Center4 requires the four center cells (shaded) to all differ from each other - only 4 of the 6 symbols are involved, so unlike the region rules above, no symbol is required to appear. Right: Corners4 imposes the same all-different requirement on the four corner cells instead.
Figure 11: Two admissible configurations of the world {BoxesRect2x3,RowLink(1,6,k=3)} on top of the Latin-square base (thick lines mark boxes; shaded rows are linked, row 6 equals row 1 shifted by 3 ). These are the two solved grids the example-based setup (Section 3.2 ) shows the model before a puzzle from this same world (Figure 1 shows one such puzzle).
Figure 12: Exposure dials (Section 3.4 ). (a) L2 accuracy on draw 1 of the no-mix split as training worlds mixing the two rule groups are added; the test worlds are the same at every level and the training sets are nested. (b) L3 accuracy on the held-out column links as training worlds containing a supporting column link are added; held-out instances and test worlds are the same at every level. Points are means over 4 seeds, bars are one standard deviation. The diamond is the description-based model trained with description dropout; hollow squares are the example-based setup on a second draw of the training worlds.
mixing
ρ
c(ρ)
L2
L3
worlds
description-based
example-based
floor
description-based
example-based
floor
0
0
0.00
67.6±5.5
82.3±1.6
62.1
58.7±3.2
77.0±2.2
59.7
5
0.01
0.05
70.0±3.2
88.6±0.8
63.8
63.6±4.8
79.3±0.9
61.9
25
0.05
0.34
89.2±0.6
92.6±0.5
64.0
70.5±2.5
78.8±1.4
62.4
100
0.20
0.64
96.6±1.4
95.8±0.3
67.7
73.4±0.8
81.8±0.3
61.2
373
0.746
0.86
98.5±1.0
97.0±0.3
70.4
77.8±3.3
82.0±1.4
60.9
Appendix
Table 5: L2 exposure dial, draw 1 of the no-mix split. Exact match in percent, mean ± standard deviation over 4 seeds. Test sets are identical at every level; training sets are nested. L0 accuracy is 97.8 to 99.5% for the description-based and example-based setups at every level.
support
supporting
L3
L1
worlds
instances (of 10)
description-based
example-based
floor
description-based
example-based
floor
0
0
34.6±6.4
65.0±0.8
52.1
98.3±0.9
98.0±0.1
75.4
5
5
48.5±2.9
70.0±0.6
52.5
98.5±0.6
98.1±0.3
75.5
25
10
48.0±7.4
77.0±1.1
53.2
98.4±0.1
97.9±0.2
74.1
100
10
79.0±7.1
86.6±1.6
57.7
98.2±0.4
97.8±0.3
74.0
228
10
79.0±5.4
90.8±2.3
56.7
97.8±0.9
97.6±0.2
68.8
Appendix
Table 6: L3 exposure dial, draw 1 . Five column links are held out at every level; the level is the number of training worlds containing one of the ten remaining column links (supporting instances). Exact match in percent, mean ± standard deviation over 4 seeds. Test sets are identical at every level. Second training draw at levels 0 , 25 and 228 ( 2 seeds): example-based 68.2±0.3 , 81.8±2.1 , 91.9±1.4 ; description-based 39.8±0.2 , 69.2±1.8 , 84.4±3.3 .
Split
Draw
description-based
example-based
floor
axis
1
36.4±3.7 / 94.0
59.4±1.8 / 97.0
45.4 / 66.3
2
37.3±3.2 / 98.6
60.3±1.4 / 97.8
50.4 / 69.5
3
35.8±2.1 / 98.0
64.0±0.2 / 97.8
50.8 / 76.8
row-pair
1
44.9±3.5 / 97.3
72.2±0.5 / 97.0
57.7 / 67.4
2
41.4±4.8 / 97.8
69.6±1.3 / 96.4
55.9 / 68.6
3
44.9±0.4 / 98.8
69.4±1.6 / 97.5
61.6 / 66.8
Appendix
Table 7: Further held-out sets for L3, three draws each. Each cell gives L3 / L1 exact match in percent (for the no-mix split, L3 / L2). Mean ± standard deviation over 4 seeds. The mixed split has one draw: description-based 73.4±2.1 , example-based 81.2±0.9 , floor 55.9±0.3 on L3.
Setting
description-based
+ dropout
floor (36 / 52 tokens)
example-based
L3 dial, level 0 (unsupported)
34.6±6.4
58.8±1.6
52.1±2.3 / 53.2±0.4
65.0±0.8
axis draw 1 (unsupported)
36.4±3.7
53.9±2.2
45.4±0.1 / 46.0±2.0
59.4±1.8
no-mix draw 1, L2
67.6±5.5
71.8±2.2
63.1±1.8 / 64.0±1.3
82.3±1.6
no-mix draw 1, L3
58.7±3.2
66.6±2.1
61.7±1.6 / 62.9±0.2
77.0±2.2
L3 dial, level 0, L1
98.3±0.9
96.5±0.2
75.4±0.9 / 77.7±0.5
98.0±0.1
Appendix
Table 8: Description dropout, evaluated with the description present. Exact match in percent, mean ± standard deviation over 4 seeds. The floor column gives the no-information model at 36 tokens and, after the slash, at 52 tokens (padded to the description-based sequence length).
Setting
Level
description-based, masked
+ dropout, masked
floor at 52 tokens
L3 dial, level 0
L3
28.0±2.9
52.4±2.0
53.2
L1
37.4±4.8
78.4±0.6
77.7
L0
33.3±3.8
74.7±0.5
72.8
Appendix
Table 9: Evaluation with the description replaced by null tokens at test time, exact match in percent. Mean ± standard deviation over 4 seeds. On the L3 dial at level 0 , the dropout model matches the 52 -token no-information model to within 2 points; the ordinary description-based model collapses.
Control
axis
row-pair
no-mix
mixed
description-based at 52 tokens (reference)
36.4
44.9
58.7
73.4
description-based padded to 108 tokens
27.9±1.6
55.3±5.0
58.5±1.4
67.5±3.8a
no-information at 36 tokens
45.4
57.7
61.7
55.9
no-information at 52 tokens
46.0±2.0
58.8±0.0
62.9±0.2
not run
composed rule vectors
36.0±5.8
57.9±10.2
53.7±5.1b
70.8c
Appendix
Table 10: Length and mechanism controls, draw 1 of each split, L3 exact match in percent, 4 seeds. Parameter counts: 1.09 M at 36 tokens, 1.11 M at 52 , 1.25 M at 108 . Padding the description-based prefix to the example-based length moves the three hard splits by −8.5 , +10.4 and −0.2 points, with no consistent sign. a Screening recipe, 2 seeds; the unpadded reference at that recipe is 67.9 . b L2 on the same split: 58.1±8.2 . c Screening recipe, 2 seeds.
Mechanism
L0
L1
L3
composed rule vectors
99.1
98.3
70.8
cross-attention from cells to description tokens
98.5
97.2
65.6
description tokens in the sequence (padded)
99.0
96.2
67.5
spatial field (did not converge)
92.4
91.5
60.5
generated per-layer modulation (FiLM; failed)
69.9
73.7
57.7
Appendix
Table 11: Injection mechanisms for the rule description, mixed split, screening recipe ( 12 epochs, cosine decay), 2 seeds. Exact match in percent at L0 / L1 / L3. The three working mechanisms are within 2 points of each other on L1.
old split
new split
old training code
65.8
95.0
new training code
66.5
98.5
Appendix
Table 12: Where the earlier L1 result for the description-based setup came from: training code (old / new) by split (old / new), L1 exact match in percent, 2 seeds per cell except the top-left one ( 25 runs).
Exposure
Setup
value shift (links)
uniqueness
parity
aggregate
0%
description-based
75.8
66.3
34.2
58.7
0%
example-based
93.2
74.6
63.1
77.0
74.6%
description-based
98.3
83.8
51.2
77.8
74.6%
example-based
96.8
79.6
69.6
82.0
Appendix
Table 13: L3 exact match in percent by rule family of the held-out instance, L2-dial split, 4 seeds, ten held-out worlds per family, at the lowest and the natural exposure level.
Figure 13: The reasoning engine, used unchanged across the three setups; only the input sequence (top box) differs between them. f is the 2 -layer, 256 -dimensional MLP-Mixer-style block stack described next, shared between the two update equations.