Systems & Complexity
Causal Loop Diagram
A visual mapping tool from systems dynamics that traces how variables influence each other in feedback loops
Systems ThinkingThe encyclopedia
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Mathematics & Statistics
Mean
The arithmetic average: sum all values and divide by count
Quantitative ModelsMathematics & Statistics
Median
The middle value when data is sorted from lowest to highest—exactly half the values fall above and half below
Quantitative ModelsMathematics & Statistics
Mode
The most frequently occurring value in a dataset
Quantitative ModelsMathematics & Statistics
False Positive
A test result that incorrectly indicates the presence of a condition—saying 'yes' when the true answer is 'no.' In medicine, a false positive means diagnosing a disease that isn't there
Quantitative ModelsMathematics & Statistics
False Negative
A test result that incorrectly indicates the absence of a condition—saying 'no' when the true answer is 'yes.' In medicine, a false negative means missing a disease that's actually present
Quantitative ModelsMathematics & Statistics
Type I Error
Seeing something that isn't there—concluding an effect or pattern exists when it doesn't
Quantitative ModelsMathematics & Statistics
Type II Error
Failing to detect something real—concluding there is no effect when one actually exists
Quantitative ModelsMathematics & Statistics
Specificity
In statistics and diagnostics: the proportion of TRUE NEGATIVES correctly identified—the ability of a test to correctly identify those who DO NOT have the condition
Quantitative ModelsMathematics & Statistics
Confounding Variable
A hidden third variable that influences both the apparent cause and the apparent effect, creating a spurious correlation between them
Quantitative ModelsMathematics & Statistics
Randomized Controlled Trial
The gold standard methodology for establishing causation: randomly assign subjects to treatment and control groups, apply the intervention to only the treatment group, and compare outcomes
Quantitative ModelsMathematics & Statistics
Data Dredging
Searching through large datasets for statistically significant patterns without pre-specified hypotheses, then presenting the 'discoveries' as if they were predicted in advance
Quantitative ModelsManagement & Organizations
10x (Force Multiplier)
The observation that in knowledge work, the best performers are not 10% better but 10x more productive than average
Leadership ModelsManagement & Organizations
Empowerment
Giving people the authority, resources, and information to make decisions within their domain rather than requiring approval from above
Motivation & CultureManagement & Organizations
Promotability
The observation that the skills that get someone promoted are often different from the skills needed to succeed at the next level
Team DynamicsManagement & Organizations
Mythical Man-Month
Fred Brooks's insight that adding people to a late software project makes it later
Team DynamicsManagement & Organizations
Culture
The set of unwritten rules, shared assumptions, and behavioral norms that determine 'how things actually work here' as opposed to 'how we say things work.' Culture is revealed not by values posters but by what gets rewar…
Motivation & CultureManagement & Organizations
Values
The explicit or implicit principles that guide an organization's decisions when trade-offs arise
Motivation & CultureManagement & Organizations
Perspective-Taking
The deliberate cognitive act of imagining a situation from another person's viewpoint, including their knowledge, beliefs, incentives, and constraints
Leadership ModelsBusiness & Product Strategy
Customer Development
Steve Blank's methodology for validating business hypotheses through direct customer interaction before building products
Product & GrowthBusiness & Product Strategy
Constraint (Theory of Constraints)
Goldratt's insight that every system's output is limited by its most constrained element—the bottleneck that determines overall throughput
Product & GrowthAging & Legacy
Erikson's Generativity vs. Stagnation Framework
Erik Erikson identified the seventh psychosocial stage (roughly ages 40-65) as the tension between generativity — contributing to the next generation through mentoring, creating, or nurturing — and stagnation, where adul…
Developmental StagesAging & Legacy
Legacy Letter Framework
A legacy letter (also called an ethical will) is a structured document that transmits values, life lessons, hopes, and blessings to loved ones — distinct from a legal will that transfers assets
Legacy PlanningAging & Legacy
Third Act Reinvention
The Third Act model reframes the post-career decades (roughly 60+) not as decline or retirement but as a distinct developmental stage with unique strengths: accumulated pattern recognition, emotional regulation, freedom…
Life TransitionsAging & Legacy
Wisdom Crystallization
Raymond Cattell's distinction between fluid intelligence (novel problem-solving, processing speed) and crystallized intelligence (accumulated knowledge, vocabulary, pattern recognition) reveals a crucial aging dynamic: w…
Cognitive DevelopmentAging & Legacy
Successful Aging Model (Rowe & Kahn)
John Rowe and Robert Kahn's influential model defines successful aging through three intersecting criteria: (1) low probability of disease and disease-related disability, (2) high cognitive and physical functional capaci…
Health & LongevityAging & Legacy
Selective Optimization with Compensation (Baltes)
Paul Baltes' SOC model describes how people maintain effective functioning despite age-related losses through three coordinated strategies: Selection (narrowing goals and domains to focus on what matters most), Optimizat…
Cognitive DevelopmentAging & Legacy
Life Review Therapy (Butler)
Robert Butler's life review theory, introduced in 1963, reframed reminiscence in older adults from a symptom of cognitive decline to a crucial developmental process
Developmental StagesAging & Legacy
Socioemotional Selectivity Theory
Laura Carstensen's theory proposes that as people perceive their time horizon as limited — whether due to aging, illness, or other factors — they shift their goals from information-seeking and network expansion toward em…
Social & EmotionalAging & Legacy
Disengagement vs. Activity Theory Debate
Two competing theories of aging have shaped policy and practice for decades
Social & EmotionalAging & Legacy
Compressed Morbidity
James Fries' compressed morbidity hypothesis (1980) proposes that the ideal aging trajectory compresses illness and disability into the shortest possible period before death, rather than extending the total lifespan
Health & LongevityAging & Legacy
Age-Related Positivity Effect
Older adults consistently show a cognitive bias toward positive over negative information — they remember positive images better than negative ones, attend more to positive faces, and recall positive memories more readil…
Social & EmotionalAging & Legacy
Elderhood as Developmental Stage
Bill Thomas and other gerontologists argue that elderhood (roughly 75+) is a distinct developmental stage — not merely 'late adulthood' but a qualitatively different period with its own developmental tasks, gifts, and ch…
Developmental StagesAging & Legacy
Ethical Will Framework
An ethical will (distinct from a legal will) is a document that transmits moral and spiritual legacy — values, beliefs, life lessons, hopes, apologies, and blessings — rather than material assets
Legacy PlanningAging & Legacy
Generative Fathering/Mothering
Generative fathering (Dollahite, Hawkins & Brotherson) and generative mothering extend Erikson's generativity concept specifically to parenting, arguing that the highest form of parenting is not protectiveness or provisi…
Developmental StagesAging & Legacy
The U-Curve of Happiness in Aging
Large-scale studies across dozens of countries consistently find a U-shaped pattern in life satisfaction: happiness starts relatively high in youth, declines through the 30s and 40s to a nadir around ages 45-50, then ris…
Social & EmotionalAging & Legacy
Retirement Identity Crisis
For knowledge workers whose identity is deeply fused with their professional role, retirement triggers not relaxation but an identity crisis
Life TransitionsAging & Legacy
Senior Moment vs. Cognitive Reserve
The popular concept of 'senior moments' — brief lapses in memory or word-finding — masks a more nuanced reality described by cognitive reserve theory
Cognitive DevelopmentAging & Legacy
Centenarian Studies and Blue Zones Principles
Dan Buettner's Blue Zones research identified five regions where people live measurably longer, healthier lives: Okinawa (Japan), Sardinia (Italy), Nicoya (Costa Rica), Ikaria (Greece), and Loma Linda (California, Sevent…
Health & LongevityAging & Legacy
Fourth Age Challenges
Peter Laslett distinguished the Third Age (active post-career life, roughly 65-80) from the Fourth Age (roughly 80+), when the body and mind begin to impose hard limits on independence
Developmental StagesAging & Legacy
Mentorship Legacy Model
The Mentorship Legacy Model proposes that the most durable form of professional legacy is not what you built but whom you developed
Legacy PlanningAttention & Contemplative Practice
Open Monitoring Meditation
Open Monitoring (OM) meditation is a practice where the meditator maintains broad, non-reactive awareness of whatever arises in experience — thoughts, sensations, emotions, sounds — without selecting any particular objec…
Meditation TechniquesAttention & Contemplative Practice
Focused Attention Meditation
Focused Attention (FA) meditation involves sustaining attention on a chosen object — typically the breath, a mantra, a visual image, or a bodily sensation — and repeatedly returning attention to that object when the mind…
Meditation TechniquesAttention & Contemplative Practice
Default Mode Network Theory
The Default Mode Network (DMN) is a set of brain regions (medial prefrontal cortex, posterior cingulate cortex, angular gyrus, hippocampus) that activate when the mind is not engaged in external tasks — during mind-wande…
Neuroscience of AttentionAttention & Contemplative Practice
Attention Restoration Theory (Kaplan) Applied
Stephen and Rachel Kaplan's Attention Restoration Theory (ART) distinguishes two types of attention: directed attention (voluntary, effortful, and depletable — used for focused work) and involuntary attention (effortless…
Attention ScienceAttention & Contemplative Practice
Flow State Model (Csikszentmihalyi) Applied to Work
Mihaly Csikszentmihalyi's flow model describes a state of complete absorption where self-consciousness dissolves, time perception alters, and performance peaks
Peak PerformanceAttention & Contemplative Practice
Mindfulness-Based Stress Reduction (Kabat-Zinn)
Jon Kabat-Zinn's MBSR program, developed at UMass Medical School in 1979, systematically adapted Buddhist mindfulness practices for secular clinical use
Applied MindfulnessAttention & Contemplative Practice
Contemplative Inquiry
Contemplative inquiry is a structured practice of holding a question in awareness without rushing to answer it — allowing insight to emerge from sustained attention rather than analytical forcing
Contemplative FrameworksPage 29 of 50 · 1345–1392 of 2,375 models