3 ♠scale 13 of 89
HOLDS
it stands
Why Order the values F < U < T: AND is the lower, OR is the higher, NOT flips the order.
Term strong Kleene connectives
Cost Cheap and uniform, but unknown spreads through a formula quickly.
Here Three values give 9 cells per connective, all built from min and max.
Arbitorium ARB-52 · journal: ________
2 ♠scale 6 of 89
FAILS
it falls
Why When p is unknown, p or not-p is unknown: the law of excluded middle is lost.
Term K3, after Stephen Kleene
Cost You gain an honest unknown and lose some classical theorems.
Here A three-valued evaluator can return non liquet instead of guessing.
Arbitorium ARB-52 · journal: ________
A ♠scale 0 of 89
HOLDS
it stands
Why Classical logic is two-valued: each sentence gets exactly one of true or false.
Term bivalence, from Latin bis, twice
Cost It forces an answer even where the evidence is missing.
Here A plain if/else has no third branch; the usage experiments add one.
Arbitorium ARB-52 · journal: ________
6 ♠scale 34 of 89
HOLDS
it stands
Why An argument is valid if, whenever the premises are designated, so is the conclusion.
Term designated values
Cost Change what is designated and you change which arguments are valid.
Here Our verdict holds is the designated one: only a holds supports the next step.
Arbitorium ARB-52 · journal: ________
5 ♠scale 27 of 89
HOLDS
it stands
Why L3 sets U implies U to true, so p implies p stays a law; K3 leaves it unknown.
Term L3, Jan Lukasiewicz, 1920
Cost More classical laws survive, but the arrow is less uniform.
Here Choose the arrow before building the evaluator: it changes what a rule can conclude.
Arbitorium ARB-52 · journal: ________
4 ♠scale 20 of 89
HOLDS
it stands
Why Flipping what you do not know tells you nothing new.
Term NOT U = U
Cost Unknown is a fixed point: negation cannot resolve it.
Here Denying a claim does not turn a non liquet into a holds.
Arbitorium ARB-52 · journal: ________
9 ♠scale 54 of 89
FAILS
it falls
Why Excluded middle: "p or not-p" is a theorem. Bivalence: every sentence is true or false. Supervaluationism keeps the first and drops the second.
Term LEM versus bivalence
Cost Keeping one without the other is subtle.
Here Say which one you are dropping when you add a third value.
Arbitorium ARB-52 · journal: ________
8 ♠scale 47 of 89
HOLDS
it stands
Why LP adds "both" as a designated third value, so a contradiction does not explode.
Term paraconsistent logic; LP, Graham Priest
Cost You can reason about inconsistent data but lose disjunctive syllogism.
Here Two sessions can record opposite facts; keep both, delete neither.
Arbitorium ARB-52 · journal: ________
7 ♠scale 41 of 89
HOLDS
it stands
Why From P and not-P, any Q follows.
Term ex falso quodlibet
Cost One inconsistency in the premises makes the whole system useless.
Here A log that may hold a contradiction needs a logic that survives it.
Arbitorium ARB-52 · journal: ________
Q ♠scale 75 of 89
NON LIQUET
it is not clear
Why In classical logic it is a contradiction; in K3 it can be unknown; in LP it is both.
Term the Liar paradox
Cost Each repair changes what else you can say.
Here A record that describes its own reliability needs a rule for itself.
What would settle it Which logic you adopt; the sentence alone does not decide.
Arbitorium ARB-52 · journal: ________
J ♠scale 68 of 89
FAILS
it falls
Why It means 'it is not clear': the Roman juror's verdict when the evidence does not settle the case.
Term non liquet, from liquere, to be clear
Cost A third verdict is honest but gives no ruling.
Here On our tiles, non liquet says what would settle it.
Arbitorium ARB-52 · journal: ________
10 ♠scale 61 of 89
NON LIQUET
it is not clear
Why Aristotle's future contingents: the answer depends on the logic. Lukasiewicz built L3 to leave it open.
Term future contingents, De Interpretatione 9
Cost Leaving it open denies determinism; closing it asserts it.
Here A claim about next week's traffic is non liquet until the traffic arrives.
What would settle it A choice of logic and of a theory of time; the data cannot settle it.
Arbitorium ARB-52 · journal: ________
2 ♥scale 8 of 89
HOLDS
it stands
Why Ambiguous grammars exist; the dangling else is the classic case.
Term ambiguous grammar
Cost Fixing it costs extra rules or a convention.
Here A precedence table is a convention that settles ambiguity.
Arbitorium ARB-52 · journal: ________
A ♥scale 1 of 89
HOLDS
it stands
Why The lexer groups characters into words of the language: numbers, names, symbols.
Term lexical analysis
Cost A separate pass is simple but cannot see grammar context.
Here It is where the character + becomes the token ADD.
Arbitorium ARB-52 · journal: ________
K ♠scale 82 of 89
NON LIQUET
it is not clear
Why It is independent of ZFC: Goedel (1940) showed it cannot be refuted, Cohen (1963) that it cannot be proved.
Term CH, Cantor, 1878
Cost Settling it means adding axioms, which is a choice, not a discovery.
Here Some questions are non liquet by proof, not by lack of effort.
What would settle it Only a new axiom, accepted by the field.
Arbitorium ARB-52 · journal: ________
5 ♥scale 29 of 89
FAILS
it falls
Why That is lexical scope. Dynamic scope looks up the call stack.
Term lexical versus dynamic scope
Cost Lexical is predictable; dynamic is flexible but hard to reason about.
Here A Tris-Trik lane copies its globals, so its names cannot reach sideways.
Arbitorium ARB-52 · journal: ________
4 ♥scale 22 of 89
HOLDS
it stands
Why Each operator pulls on its neighbours with a number; the stronger pull wins.
Term top-down operator precedence, Vaughan Pratt, 1973
Cost Compact, but harder to read than a grammar.
Here Crafting Interpreters builds one in a few dozen lines.
Arbitorium ARB-52 · journal: ________
3 ♥scale 15 of 89
FAILS
it falls
Why It drops the punctuation and keeps the structure; the concrete tree keeps it all.
Term AST versus concrete syntax tree
Cost Dropping punctuation loses formatting, so a pretty-printer needs it back.
Here The house compiler converts a fixed six-node workflow, not free text.
Arbitorium ARB-52 · journal: ________
8 ♥scale 49 of 89
HOLDS
it stands
Why A function plus the environment it was born in.
Term closure
Cost Captured variables live as long as the closure does.
Here The Arbitorium page functions close over the game state.
Arbitorium ARB-52 · journal: ________
7 ♥scale 42 of 89
HOLDS
it stands
Why Operands wait on a stack; each instruction takes its inputs from the top.
Term stack VM, bytecode
Cost Compact code, but more instructions than a register machine.
Here Tris-Trik's VOTE pops three trits and pushes one.
Arbitorium ARB-52 · journal: ________
6 ♥scale 35 of 89
NON LIQUET
it is not clear
Why Studies disagree, and they mix up language, team and task.
Term static versus dynamic typing
Cost Each side has strong stories and thin evidence.
Here The Python tools here lean on tests, not types.
What would settle it A controlled study across comparable teams and tasks.
Arbitorium ARB-52 · journal: ________
J ♥scale 70 of 89
HOLDS
it stands
Why Compile it once with some other compiler; afterwards it compiles itself.
Term bootstrapping, self-hosting
Cost The chain of trust starts at the first compiler (Thompson's Trusting Trust).
Here The first build of anything here is put on the record with a hash.
Arbitorium ARB-52 · journal: ________
10 ♥scale 63 of 89
HOLDS
it stands
Why The house ternary language answers a claim with one of three values, not two.
Term Tris-Trik
Cost Every consumer of an answer must handle the third value.
Here The usage experiments return the same three.
Arbitorium ARB-52 · journal: ________
9 ♥scale 56 of 89
FAILS
it falls
Why Turing (1936): no general procedure decides halting.
Term the halting problem
Cost So program analyses are approximate: they say maybe.
Here Maybe is exactly the non liquet a sound analyser must be allowed to return.
Arbitorium ARB-52 · journal: ________
A ♦scale 3 of 89
HOLDS
it stands
Why Whatever the other does, defecting pays you more.
Term dominant strategy
Cost Both defecting leaves both worse off than both cooperating.
Here A shared GPU with no gate invites every job to grab it.
Arbitorium ARB-52 · journal: ________
K ♥scale 83 of 89
NON LIQUET
it is not clear
Why Tests show a bug's presence, never its absence (Dijkstra). Only a proof against a specification would settle it.
Term program correctness
Cost A proof usually costs more than the program.
Here Every build here reports 'N tests pass, 25 reruns', never 'no bugs'.
What would settle it A proof against a written specification.
Arbitorium ARB-52 · journal: ________
Q ♥scale 77 of 89
NON LIQUET
it is not clear
Why It depends on the allocation pattern, the collector and the hardware.
Term garbage collection versus manual management
Cost Throughput against predictable pauses.
Here The Python tools here are collected; the C side is manual. Neither is ruled better.
What would settle it A benchmark on the real workload, which settles it for that workload only.
Arbitorium ARB-52 · journal: ________
4 ♦scale 23 of 89
HOLDS
it stands
Why Moves form a tree; a strategy is a plan for every node you could reach.
Term extensive form, game tree
Cost Trees grow explosively with every extra branch.
Here The Arbitorium is a game tree: your path is a strategy, the held branches are moves not made.
Arbitorium ARB-52 · journal: ________
3 ♦scale 17 of 89
FAILS
it falls
Why In the prisoner's dilemma the equilibrium is worse for both than cooperation.
Term Pareto efficiency
Cost Equilibrium is stable, not good.
Here A fail-closed rule can be stable and still inconvenient.
Arbitorium ARB-52 · journal: ________
2 ♦scale 10 of 89
HOLDS
it stands
Why Nash (1950): a set of strategies where nobody gains by changing alone.
Term Nash equilibrium
Cost It exists, but may be hard to find, and there may be many.
Here The one-branch rule has a best reply at every fork.
Arbitorium ARB-52 · journal: ________
7 ♦scale 44 of 89
NON LIQUET
it is not clear
Why Computational irreducibility is believed (Wolfram) but unproven.
Term Rule 30, cellular automaton
Cost If true there is no shortcut; if false a shortcut exists.
Here Rule 30 is among the house's math files.
What would settle it A proof or a shortcut.
Arbitorium ARB-52 · journal: ________
6 ♦scale 37 of 89
NON LIQUET
it is not clear
Why Sandpile models show it can; whether it is the general cause is debated.
Term SOC, Bak, Tang and Wiesenfeld, 1987
Cost A strong idea that is hard to test on real data.
Here Heavy-tailed usage would not by itself prove it.
What would settle it Direct tests on each specific system, one at a time.
Arbitorium ARB-52 · journal: ________
5 ♦scale 30 of 89
HOLDS
it stands
Why Start at the last move, decide it, then step back.
Term Zermelo, Kuhn; subgame perfection, Selten
Cost It assumes everyone is rational and knows that everyone is.
Here Work back from the end of a path to decide the fork.
Arbitorium ARB-52 · journal: ________
10 ♦scale 65 of 89
NON LIQUET
it is not clear
Why Open since 1971 (Cook); a proof either way would settle it.
Term P versus NP, a Clay Millennium Problem
Cost Most believe they differ; nobody has proved it.
Here It is the reason some searches here are bounded.
What would settle it A proof.
Arbitorium ARB-52 · journal: ________
9 ♦scale 58 of 89
FAILS
it falls
Why Big-O describes growth and ignores constants; for small n the quadratic can win.
Term asymptotic notation
Cost Ignoring constants hides real cost.
Here The pinecone has 89 scales: small enough that clarity beats cleverness.
Arbitorium ARB-52 · journal: ________
8 ♦scale 51 of 89
FAILS
it falls
Why For P(x) ~ x^-a, the mean is finite only for a above 2, the variance only for a above 3.
Term heavy tail, Pareto
Cost The average then misleads; use medians and quantiles.
Here Our latency numbers are percentiles for that reason.
Arbitorium ARB-52 · journal: ________
K ♦scale 85 of 89
HOLDS
it stands
Why The second-price (Vickrey) auction does it.
Term mechanism design; Hurwicz, Maskin, Myerson
Cost There are impossibility results: you cannot have everything.
Here The usage log records what happened, so honesty is the cheap path.
Arbitorium ARB-52 · journal: ________
Q ♦scale 78 of 89
HOLDS
it stands
Why It is the most irrational turn, so a seed never lands on an earlier seed's ray.
Term phyllotaxis; golden angle = 360 / phi squared
Cost Real plants vary; the model is an ideal.
Here The minecone puts scale m at angle m times 137.5 degrees.
Arbitorium ARB-52 · journal: ________
J ♦scale 71 of 89
HOLDS
it stands
Why A positive Lyapunov exponent means sensitive dependence on initial conditions.
Term chaos, Lorenz, 1963
Cost Long-range prediction fails even with a perfect rule.
Here A hash behaves this way on purpose: change one byte, change everything.
Arbitorium ARB-52 · journal: ________
3 ♣scale 18 of 89
FAILS
it falls
Why Fail-closed denies; fail-open allows.
Term fail-closed versus fail-open
Cost Outages lock people out.
Here The backend refuses everything if its session secret is missing.
Arbitorium ARB-52 · journal: ________
2 ♣scale 11 of 89
HOLDS
it stands
Why A part that cannot do harm cannot be made to.
Term principle of least privilege
Cost More accounts and grants to manage.
Here The guardrail worker has no delete route, and holds no token that could delete.
Arbitorium ARB-52 · journal: ________
A ♣scale 5 of 89
FAILS
it falls
Why Security is relative to a threat model: an attacker, a goal, a capability.
Term threat model
Cost Writing it down shows what you did not defend.
Here The house design names the API as the main attack vector.
Arbitorium ARB-52 · journal: ________
6 ♣scale 39 of 89
HOLDS
it stands
Why Possession is authority: the secret is the permission.
Term capability security
Cost If it leaks, so does the power.
Here The y in xx-y-zz is a secret of this kind.
Arbitorium ARB-52 · journal: ________
5 ♣scale 32 of 89
HOLDS
it stands
Why A nonce plus an expiry makes each approval good for one use.
Term nonce, replay protection
Cost The receiver has to keep state.
Here The passkey challenge spec binds one approval to one intent.
Arbitorium ARB-52 · journal: ________
4 ♣scale 25 of 89
HOLDS
it stands
Why Each link hashes the one before it, so an edit shows downstream.
Term hash chain; Merkle trees are the branching cousin
Cost It detects change; it does not prevent it.
Here The usage log and the recall anchors are chained and checked.
Arbitorium ARB-52 · journal: ________
9 ♣scale 59 of 89
FAILS
it falls
Why Side channels leak through time, power and sound, not through the maths.
Term side channel
Cost Constant-time code is harder to write.
Here Our key comparisons are constant-time for this reason.
Arbitorium ARB-52 · journal: ________
8 ♣scale 53 of 89
HOLDS
it stands
Why A wrong guess gets a believable answer, so the attacker cannot tell.
Term honey encryption, Juels and Ristenpart, 2014
Cost It needs a model of what plausible data looks like.
Here The house honey module generates decoys on the fly instead of storing them.
Arbitorium ARB-52 · journal: ________
7 ♣scale 46 of 89
FAILS
it falls
Why Kerckhoffs: assume the attacker knows the system; only the key is secret.
Term Kerckhoffs's principle, 1883
Cost Public scrutiny finds flaws you would miss.
Here The honey module's code can be public; only its key matters.
Arbitorium ARB-52 · journal: ________
Q ♣scale 80 of 89
NON LIQUET
it is not clear
Why You cannot prove a negative about what you have not found.
Term unknown unknowns
Cost Time and review lower the risk but never close it.
Here Every report here says what was searched and what was not.
What would settle it Nothing finite; only more review lowers the risk.
Arbitorium ARB-52 · journal: ________
J ♣scale 73 of 89
HOLDS
it stands
Why Least privilege applied to delegation.
Term scoped grant, delegation
Cost More machinery to issue and check grants.
Here The house design has the AI hold a signed Grant, not the token.
Arbitorium ARB-52 · journal: ________
10 ♣scale 66 of 89
NON LIQUET
it is not clear
Why No complete defence is known; an attacker can rephrase.
Term prompt injection
Cost Filters catch the known and miss the new.
Here The house treats untrusted text as data, never as instructions.
What would settle it A proof of a complete defence, or a demonstrated attack that breaks any given one.
Arbitorium ARB-52 · journal: ________
◆ ARBITORIUM

Back of the verdicts

This card backs the verdicts card.

◆ ARBITORIUM

Back of the rules

This card backs the rules card.

K ♣scale 87 of 89
NON LIQUET
it is not clear
Why Many eyes help only if the eyes look: Heartbleed sat in open code for years.
Term open source and security
Cost Both sides have strong examples.
Here The ternary public copy is scrubbed before it is published.
What would settle it Careful measurements per project, not a general ruling.
Arbitorium ARB-52 · journal: ________