Mental Model
Two-by-Two Matrix
A representation crossing two relevant dimensions, each divided into two categories, to reveal four combinations
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Mental Model
Two-Eyed Seeing (Etuaptmumk)
Etuaptmumk (Two-Eyed Seeing) is a Mi'kmaw principle articulated by Elder Albert Marshall that involves learning to see from one eye with the strengths of Indigenous knowledge and from the other eye with the strengths of…
Mental Model
Two-Factor Authentication Thinking
Two-factor authentication (2FA) requires two independent verification types: something you know (password), something you have (phone, key), or something you are (biometric)
Mental Model
Two-Front War
The strategic principle that fighting on two fronts simultaneously divides resources, attention, and energy—dramatically reducing effectiveness on both
Mental Model
Two-Minute Rule (Meetings)
An adaptation of David Allen’s GTD heuristic: when processing work, a needed action that is very brief may cost less to complete than to track and revisit
Mental Model
Two-Minute Rule for Habits
The Two-Minute Rule for habits states that any new habit should be downsized until done in two minutes or less
Cognitive Move
two-panel reject and prefer
Two stacked slots. The upper one holds what is being waved away, the lower one holds what is being chosen. Position does all the work: down is better, and the posture drawn in the upper panel supplies a tone toward the rejected option that you never wrote. It compresses a whole comparison into one glance, and it leaves no room for the criteria that made the choice, so the reader sees the verdict and never the reasoning.
Mental Model
Two-Pizza Teams (Amazon)
Amazon’s principle of keeping teams small and giving them focused, sustained ownership of a product or service
Mental Model
Two-sided Market
A platform setting where participation and interactions across distinct groups affect demand, so the allocation of prices and incentives between groups can matter alongside their total level
Mental Model
Type I Error
Seeing something that isn't there—concluding an effect or pattern exists when it doesn't
Mental Model
Type II Error
Failing to detect something real—concluding there is no effect when one actually exists
Cognitive Move
Type Objective
Decide whether the goal should demand a result, a process, learning, maintenance, or prevention based on how much you actually know.
Cognitive Move
Typed arrows
Every line between two items has to declare which relation it carries: causes, converts into, precedes, contradicts. One arrow shape per relation kind, defined once. If you cannot name what an edge means, delete it instead of drawing a vague connector.
Cognitive Move
Typed edges
Every line you draw gets a label naming what actually flows and which way it points. A plain "connected to" line hides the difference between who organizes and who tags along, so it cannot tell you which tie matters when someone leaves.
Mental Model
Tyranny of Metrics (Muller)
Jerry Muller's documentation of how metric fixation—the belief that all important outcomes can and should be measured, and that measurement improves performance—systematically distorts organizational behavior
Mental Model
Tyranny of Small Decisions
Alfred Kahn's concept that a series of individually rational, small decisions can aggregate into a collectively irrational, large outcome that NO individual decision-maker would have chosen if presented with the total re…
Cognitive Move
U — Unspoken default
Doing nothing, waiting, or quitting is secretly steering your decision because nobody has named it as an option.
Mental Model
U-Curve of Happiness (Midlife Dip and Later-Life Rise)
Some studies report a U-shaped association between age and measures such as life satisfaction, with lower average values in midlife and higher values at older ages
Mental Model
Ubuntu (I Am Because We Are)
Ubuntu is the Southern African philosophical concept, expressed in the Nguni proverb 'Umuntu ngumuntu ngabantu' (a person is a person through other persons), that human identity, dignity, and flourishing are fundamentall…
Mental Model
Ubuntu Leadership Model
Ubuntu leadership, articulated by scholars like Lovemore Mbigi and Reuel Khoza, defines leadership not as individual authority or charisma but as the capacity to cultivate the humanity and potential of others
Mental Model
Ujamaa (Cooperative Economics and Familyhood)
Ujamaa, meaning 'familyhood' or 'extended family' in Kiswahili, is the East African economic philosophy articulated by Julius Nyerere in the 'Arusha Declaration' (1967) as the foundation of Tanzanian socialism
Mental Model
Ultimate Responsibility
Ultimate responsibility concerns a demanding form of moral responsibility that appears to require responsibility for the character from which one acts
Mental Model
Ultra-Processed Food Continuum (NOVA Classification)
The NOVA classification, developed by Carlos Monteiro at University of São Paulo, categorizes foods by processing level: Group 1 (unprocessed—fruits, vegetables, meat), Group 2 (culinary ingredients—oils, butter, salt),…
Mental Model
Ultradian Rhythm Management for Knowledge Work
Ultradian rhythms are roughly 90-minute cycles of higher and lower arousal that occur throughout the day, discovered by sleep researcher Nathaniel Kleitman (who also identified REM sleep)