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Digital library · In preparation
Hints and answers
without losing the mystery.
Each edition will be linkable with its code. Reveal a hint when needed, check the reasoned solution and keep your progress.
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RASTROS · First steps
Ten cases to get started.
Download two free Spanish-language RASTROS booklets with colour puzzles, hints and solutions. The cases are also available in English on this site.
Downloadable puzzles and solutions →Graded help
A hint
is not the solution.
A good hint returns the reader to the exact point where they got stuck, without solving the case. Writing one is harder than writing the solution: you must know what a reader halfway through needs and give them only that.
That is why FALSUM's hints are tiered, rather than a single button. The first points to where to look without revealing what is strange. The second names the incompatibility but lets the reader explain it. The third gives the full reasoned solution and argument.
Order matters because most sticking points resolve at the first step. A reader given the whole answer when they only needed a nudge loses the case: there is nothing left to solve. That is why solutions are kept separate from cases, on paper too.
What a reasoned solution is
It is not enough
to guess correctly.
A reasoned solution does more than name the culprit: it explains why nobody else could be responsible. It walks through the clues, shows the contradiction and rules out the alternatives one by one.
It serves two purposes. First, it checks whether you reached the answer by the right route: in deduction, a correct answer for the wrong reason is not a solved case. Second, it helps you learn from mistakes: seeing where the reasoning went wrong teaches more than solving three cases in a row.
To see a complete case with its premise, contradiction and explained solution, the guide to what a deduction puzzle book is includes a full worked example.