In classical logic every statement is either true or false, with no third value.

In Kleene's strong three-valued logic, p or not-p is always true.

In K3, with false below unknown below true, AND takes the minimum and OR takes the maximum.

In K3, the negation of unknown is unknown.

In Lukasiewicz's three-valued logic, unknown implies unknown is true.

In K3 and L3 the only designated value, the one a valid argument must preserve, is true.

In classical logic, a contradiction implies every statement.

In Priest's logic LP, a statement can be both true and false without everything following.

The law of excluded middle and the principle of bivalence say the same thing.

'There will be a sea battle tomorrow' is already true or already false today.

'Non liquet' means 'it is false'.

The sentence 'this sentence is false' is true.

The continuum hypothesis (no set is larger than the integers and smaller than the reals) is true.

A lexer turns a stream of characters into tokens before the parser runs.

One string can have two valid parse trees under the same grammar.

The abstract syntax tree keeps every parenthesis and semicolon from the source.

A Pratt parser handles operator precedence by giving each operator a binding power.

Under dynamic scope, a variable is looked up where the function was written.

Static typing reduces bugs in practice more than dynamic typing does.

A stack machine evaluates 2 + 3 by pushing 2, pushing 3, then an ADD that pops two and pushes one.

A closure keeps the variables of the scope where it was created.

A compiler can always tell whether the program it compiles will halt.

Tris-Trik's three values are supported, contradicted and non liquet.

A compiler for a language can be written in that same language.

Garbage collection is faster than manual memory management.

This program has no remaining bugs.

In the prisoner's dilemma, defecting is a dominant strategy for each player.

Every finite game has at least one Nash equilibrium if mixed strategies are allowed.

A Nash equilibrium is always the best outcome for the players together.

In an extensive-form game, a player picks one branch at each decision point.

Backward induction finds an equilibrium in any finite game of perfect information.

Self-organised criticality explains most power laws seen in nature.

Rule 30, a one-dimensional cellular automaton, cannot be predicted any faster than by running it.

A power-law distribution has a finite average for every exponent.

An O(n log n) algorithm is faster than an O(n squared) one on every input.

P equals NP.

In a chaotic system, tiny differences in the starting state grow exponentially.

The golden angle, about 137.5 degrees, spaces seeds so that no spoke lines up.

A mechanism can be designed so that telling the truth is each player's best strategy.

A system can be called secure without saying who it is secure against.

Least privilege gives each part only the access its job needs.

A fail-closed system allows access when its check cannot run.

Changing one entry in a hash chain changes every later link.

A signed message cannot be replayed if it carries a one-time number that the receiver remembers.

Holding an unguessable capability is enough authority to use it, with no identity check.

A secret algorithm is as safe as a public one that uses a secret key.

Honey encryption returns plausible fake plaintexts for wrong keys instead of an error.

A mathematically correct cipher cannot leak its key through timing.

Prompt injection can be fully prevented by filtering the input.

An AI holding a scoped, time-boxed grant can do less damage than one holding the raw token.

This system has no unknown vulnerabilities.

Open-source code is more secure than closed-source code.