Constraints

You have finite resources. Every allocation is a choice. Understanding your constraints is the foundation of realistic planning.

The Four Constraints

ConstraintRenewable?Expandable?Notes
TimeNoNo24 hours/day, non-negotiable
EnergyYes (daily)SomewhatSleep, health, motivation
MoneyYes (earned)YesIncome, savings, investments
AttentionYes (daily)SomewhatFocus, cognitive load

Time

The hardest constraint. Cannot be saved, borrowed, or created. Only spent.

Implication: Ruthless prioritization. Every “yes” is a “no” to something else.

Energy

Renewable but limited daily. Depletes with use, restores with rest.

Implication: Match task difficulty to energy level. Protect peak energy for important work.

Money

Fungible and storable. Can buy time (outsourcing) and sometimes energy (convenience).

Implication: Money is frozen time. Spend it on things that free time or energy.

Attention

The scarcest resource in the information age. Every notification, every tab, every interruption costs attention. Herbert Simon called this “bounded rationality”—we have limited cognitive resources for processing information (Simon, 1971).

Implication: Guard attention like money. It’s more valuable.

Constraint Interactions

TradeExampleCost
Money → TimeHire help, take a cabFinancial
Time → MoneyWork overtime, side hustleTime/energy
Attention → QualityDeep workOther tasks neglected
Energy → TimePower throughTomorrow’s energy

The Bottleneck Principle

System output is limited by the tightest constraint. Optimizing non-bottlenecks is waste (Goldratt & Cox, 1984).

Ask: What’s actually limiting me right now?

If bottleneck is…Don’t…Do…
TimeAdd more tasksCut scope, delegate
EnergyPush harderRest, simplify
MoneySpend on nice-to-havesInvest in bottleneck relief
AttentionMultitaskSingle-task, eliminate distractions

Cross-Domain Applications

DomainPrimary ConstraintSolution
HealthTime, energyEfficient protocols, protect sleep
WealthMoney (early), time (later)Income growth → automation
SocialTime, attentionQuality over quantity
MeaningAttention, energyDeep work, rest

Decision Criteria

Before any commitment, ask:

  1. What does this cost in time?
  2. What does this cost in energy?
  3. What does this cost in money?
  4. What does this cost in attention?
  5. Is the return worth all four costs?

Know your constraints. Plan within them. Expand them where possible. Accept them where not.

Goldratt, E. M., & Cox, J. (1984). The Goal: A Process of Ongoing Improvement. North River Press.
Simon, H. A. (1971). Designing Organizations for an Information-Rich World. In M. Greenberger (Ed.), Computers, Communications, and the Public Interest (pp. 37–72). Johns Hopkins Press.