Questions for you:
- When you ask people to “pick a random example” or “give me a random number,” do you notice patterns in what they choose – and do those patterns tell you something about how they’re actually thinking rather than being truly random?
- In situations where you’re supposed to be making unbiased selections or random choices, how confident are you that your own mental patterns aren’t influencing the outcome?
- If you were designing a system that required human-generated randomness (like manual password creation or “random” quality checks), what safeguards would you need to prevent predictable patterns?
- When did you last mistake a pattern for randomness, or randomness for a pattern – and what were the consequences?
Organisational applications:
Password and PIN policies: Eliminate human choice wherever possible. Users asked to create “random” passwords will unconsciously follow patterns – avoiding repeated digits, preferring certain numbers (especially seven), using predictable substitutions. Implement generated passwords using proper random number generators, or use passphrase systems with randomly selected words from large dictionaries.
Quality control and inspection: Random sampling procedures handled by humans aren’t genuinely random. Inspectors unconsciously develop patterns – checking items in regular intervals, favouring certain positions, avoiding repetition. Use automated random selection for audit samples, security checks, and quality inspections to eliminate human pattern-following.
A/B testing and experimentation: Human-assigned experimental groups will show systematic bias. Researchers unconsciously assign “better” subjects to preferred conditions or distribute assignments in predictable patterns. Always use computerised randomisation for experimental design, clinical trials, and user testing to ensure genuine random assignment.
Fraud detection training: Educate staff that human-generated “random” data contains detectable patterns. Whether it’s fabricated expense reports, invented time logs, or falsified test results, people trying to create random-looking data unconsciously introduce patterns. Train analysts to recognise these telltale signs of manufactured randomness.
Further reading
Psychology of number preferences
The Psychology of Judgment and Decision Making by Scott Plous – comprehensive overview of cognitive biases in decision-making, including chapters on how humans misjudge randomness and probability, with implications for why we fail to generate truly random sequences.
The Art of Thinking Clearly by Rolf Dobelli – collection of common thinking errors including discussion of how we perceive and misunderstand randomness, with practical examples of number biases in everyday decisions.
“The predominance of seven and the apparent spontaneity of numerical choices.” by Michael Kubovy and Joseph Psotka in The American Journal of Psychology – research paper documenting heptaphilia (preference for seven) across experimental conditions, showing the preference persists even when seven is given as an example or the range is shifted.
Human randomness and pattern recognition
Thinking, Fast and Slow by Daniel Kahneman – Nobel laureate’s examination of cognitive biases, including extensive discussion of how humans see patterns in randomness and fail to recognise genuinely random sequences, particularly the clustering illusion and hot hand fallacy.
The Drunkard’s Walk by Leonard Mlodinow – explores how randomness rules our lives, with chapters on why humans cannot reliably generate or recognise random sequences, illustrated through gambling, sports, and business examples.
Fortune’s Formula by William Poundstone – history of information theory and gambling, including discussion of how humans systematically fail at generating random behaviour in games, leading to exploitable patterns.
Cultural significance of numbers
The Number Sense by Stanislas Dehaene – cognitive scientist’s examination of how brains process numbers, including research on subitising (immediately recognising quantities up to about seven) which may contribute to seven’s special psychological status.
The Secret Life of Numbers by Kate Kitagawa and Timothy Revell – explores mathematical concepts through cultural and historical lenses, including why certain numbers like seven appear so frequently in human culture, religion, and categorisation systems.
Number: The Language of Science by Tobias Dantzig – classic exploration of how humans conceptualise and use numbers, including discussion of why certain numbers hold special psychological and cultural significance across civilisations.
About the image
The image is fairly self-explanatory. The colours, however, remind me of my favourite football team.
Illustration by Matt Ballantine, 2026
Random the Book 