JustilityThinking tools
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Structure decisions, test assumptions and explore systems using local worksheets, visual maps and numerical models.
Thinking tools
Choose thinking tools for your task
Weighted decision matrix
Compare options using normalized weights, explicit ratings and a transparent weighted ranking.
Open Weighted decision matrixFirst principles thinking
Separate facts from assumptions and rebuild a testable solution from explicit constraints.
Open First principles thinkingFive whys analysis
Investigate an observed problem with an evidence-backed why chain and corrective actions.
Open Five whys analysisPre-mortem planner
Imagine project failure, prioritize plausible risks and assign preventive actions and warning signals.
Open Pre-mortem plannerWeighted decision matrix
Compare options using normalized weights, explicit ratings and a transparent weighted ranking.
Open toolFirst principles thinking
Separate facts from assumptions and rebuild a testable solution from explicit constraints.
Open toolFive whys analysis
Investigate an observed problem with an evidence-backed why chain and corrective actions.
Open toolPre-mortem planner
Imagine project failure, prioritize plausible risks and assign preventive actions and warning signals.
Open toolDecision tree builder
Build decision and chance branches, enter payoffs and calculate risk-neutral expected values.
Open toolArgument mapping canvas
Connect claims, evidence and objections in an editable local argument map.
Open toolSecond-order thinking
Explore an action, its immediate consequences and later effects in a visual consequence tree.
Open toolAssumption testing canvas
Prioritize uncertain assumptions and define experiments, thresholds, results and decision rules.
Open toolSystems iceberg explorer
Explore events, recurring patterns, structures and mental models with explicit evidence and tests.
Open toolCausal loop diagram builder
Map signed causal links, delayed effects and reinforcing or balancing feedback loops.
Open toolBayesian belief updater
Update a binary belief using explicit priors and conditional evidence likelihoods.
Open toolScenario planning studio
Explore four low/high futures across two uncertainties and define indicators and strategic responses.
Open toolMonte Carlo simulator
Simulate a seeded weighted sum of independent uncertain inputs with percentiles and a histogram.
Open toolStrategy canvas
Plot competing offerings across shared factors using editable ratings and downloadable value curves.
Open toolDecision journal
Record decisions, expectations, confidence and later outcomes in a downloadable local journal.
Open toolPrivate comes standard.
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