How does a message become a secret cipher?
An agreed rule changes the letters. Reversing the same rule restores the message.
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Text & appearance
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Detectives & Puzzles
Observe carefully, check clues and explain answers: discover puzzles and the limits of guesses.
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What can a fingerprint reveal?
Fine skin ridges leave a pattern. Clear details matter more than a quick glance.
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Why can identical patches look different?
Perception takes the surroundings into account. A checkable comparison separates appearance from properties.
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How can you find a way through a maze?
Remember junctions, test a path and return deliberately when it reaches a dead end.
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How do you solve a puzzle using clues?
Instead of guessing, rule out possibilities. Each conclusion must fit the agreed information.
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How can devices make the night visible?
Some devices amplify faint light. Others turn invisible thermal radiation into a picture.
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How do you check whether a banknote is genuine?
A similar picture is not enough. Several appropriate features need checking together.
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What lies behind Bermuda Triangle stories?
An exciting tale does not prove mysterious forces. Ask for comparable numbers and checkable circumstances.
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What can Stonehenge’s stones tell us?
A structure preserves traces of human work. Some directions fit the Sun, but we do not know all the builders’ thoughts.
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How did people build on a steep mountain?
Machu Picchu shows Inca buildings and terraces. Stepped surfaces make a slope usable differently from one continuous incline.
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How do researchers check Yeti and Nessie stories?
A drawing, a sample and its examination are different things. Good research also explains what a result cannot tell us.
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