Declarative, Procedural, and Conditional Knowledge
Declarative, Procedural, and Conditional Knowledge
Under any skill there are three separate jobs. Having one of them does not give you the other two. The first job is knowing what the thing is and what it accomplishes. The second job is running it without spending attention on the running. That is a different achievement, and it comes later. The third job is judging, in a situation you have not met before, that this is the move to use. The psychology terms for the three are declarative, procedural, and conditional.
Keeping the three apart is what makes the labels useful. When a technique you understand completely still fails in performance, the missing job tells you which practice to do next.
Core takeaways
- Every skill has three separate jobs: knowing what it is, running it automatically, and judging when to use it. Having one does not give you the others.
- This vault counts any step that is still chosen on purpose as declarative. Procedure begins only where conscious control ends.
- This vault treats conditional knowledge, the when and why, as a subset of declarative. It grows as a by-product of practice in varied contexts.
- When an understood technique fails in performance, suspect the declarative side first. The usual block is deciding which method to use and in what order.
- The test is a messy problem. A wrong method or order is a declarative gap. The right method done clumsily is a procedural gap.
- The first job comes from being told. The other two are built by doing. Start attempts early, because each person makes about five to seven of the hundreds of possible mistakes.
Where each type begins and ends
Declarative knowledge is the foundation. It covers facts, concepts, relationships, and anything that can be explained. In this vault it also covers any step still chosen on purpose. Every other type builds on it. Content-heavy subjects are almost entirely declarative. History, biology, and theory of any kind are declarative. Medicine is mixed: the facts and the diagnostic plan are declarative; the practised motor part of a procedure is not.
Procedural knowledge means automatic. Driving, native-sounding pronunciation, and fluent code are examples. The execution is so practised that it runs without thinking about the steps. The everyday name for this is muscle memory. It is not “knowing how” in the everyday sense. Taking disease facts, picking a diagnosis, and writing a plan is still choosing, reasoning, and ordering steps on purpose. That whole stretch is declarative. Procedure begins only where conscious control ends. This is where this vault draws the line. The research field does not draw it in the same place.
The automatic kind develops slowly, and only through doing. Once it is in place, the declarative scaffolding underneath it can fade. The usual example is a fluent speaker who cannot state the adjective-order rule. The production runs, and the verbal access is gone. Global Workspace and J-space explains why: the skill has left the deliberate workspace. Knowledge Mastery From Recognition to Usable Knowledge grades the declarative side of the same split. The levels stay on that page.
Conditional knowledge is knowing when and why to use what is already held. This vault treats it as a subset of declarative, because the when and why can be explained on demand. Scholars do not agree that it is a separate type. Strategy-instruction research treats the when-layer as something to teach explicitly. This vault’s stance is different and narrower. Building declarative and procedural knowledge across varied contexts, challenge types, and time pressures produces the when-layer as a by-product. It grows when context is changed on purpose. It does not grow by waiting.
Theory first, then the attempt
The theory is engaged first, through notes, analogies, connections, and critique. The skill is attempted as soon as there is enough theory to find the first mistakes. The order is working understanding, then the attempt. Rapid Skill Acquisition sets this pacing. Certainty before the first attempt is impossible. Asking more clarifying questions to reach certainty delays the attempt, and the attempt is what teaches.
Fail fast, fail safe means finding the cheap early mistake before the cost is concentrated. A messy session half a year before the deadline is cheap information. Finding the same hole in the last week puts the whole cost into that one week. Small early errors prevent the large late ones.
A skill may offer hundreds of possible mistakes. Any one person makes about five to seven of them. Those five to seven are the ones to look for. Trying to prevent the whole catalogue with what-if questions overwhelms working memory and stalls the start. The start is what reveals the five to seven.
Some tendencies come from another domain and cannot be seen from inside. A habit trained in a different skill carries over and keeps happening. An observer sees it. The person doing it does not.
The loop after an attempt is try, reflect against the declarative model, refine, retry. With a strong model of the skill, a failed attempt gives a specific question to ask. Kolbs Experiential Cycle is that loop: what happened, how it felt and why, what rule that suggests, what changes next time.
Understanding without being able to perform
A person can understand a skill completely and still fail to perform it. This gap is the reason the three-way split exists. Understanding is not performance. Knowing what to do is a small fraction of mastery. Most of the work is built through practice. Each job has a different best teacher: explanation for the first, the attempt for the other two. The fraction is a teaching rule, and no study has measured knowing-what as a tenth of mastery.
Finding which type is missing
Suspect declarative first. Even in subjects that look procedural, the usual block is deciding which method to use, in what order, for this situation. That decision is declarative. A great deal can be solved without procedure if each step can be paused and decided. Pure execution is becoming cheap to automate. The layer of approach, strategy, and judgment stays expensive. This is a reason to check the first job first. It says nothing about the future of labour.
Someone who can finish the usual practice set and then cannot solve the same problem inside a real case is missing a concept. More repetitions of the same set will not supply the concept. Interleaving for Complex Problem Solving applies this diagnosis. The test is a messy challenge. A wrong method, a wrong order, or a broken chain of reasoning is a declarative gap. The right method done clumsily is a procedural gap: a slipped calculation, a syntax bug, or stiff prose.
Match practice to that diagnosis. Retrieval methods split along the same line. Interleaving Table holds that split, and the knowledge type diagnosed above is the variable it splits on. Spaced Interleaved Retrieval is the retrieval system that takes that variable. Use the three types before the next hour of practice or the next test. Reciting them after the practice has no use.
Where this vault differs from the research
This vault’s cut is a useful diagnostic. It is not a consensus definition. A reader who treats the three names as three real, separate things will call application procedure and then add more drills of the same shape. The research field often treats application as a mix of types, and treats the when and why as teachable. Both disagreements are real. The cut is still the tool: if the steps are still being chosen, the hour is declarative.
The split that holds is explanation versus attempt. It is not person versus experience in every domain. A coach can shape procedure through feedback, demonstration, and constraint. Mental practice can move procedure a little. The direction stays the same: the first job arrives from being told, and the other two are built in the doing.
The 10/90 split and the five-to-seven-of-hundreds are this vault’s teaching numbers. They are not research findings. Varied practice is the technique for the when-layer. “No dedicated techniques” and “develops for free” are too strong as absolutes. If the next hour is still chosen step by step, and the practice is more drills of the same shape, the diagnosis was skipped. The check is the next messy problem. It exposes either a wrong approach or a right approach done clumsily.
Sorting the next hour of practice
The three types are used before the next hour of practice. An hour that can still be explained step by step is declarative, even when it looks like doing. An hour that runs without the steps being chosen is procedural. An hour that changes context on purpose is how the when-layer grows. The three names are a tool for sorting practice. Memorizing them as a list is not their use.
How to practice this
- Before the next hour of practice, ask whether each step is still chosen on purpose. If it is, count the hour as declarative, even when it looks like doing.
- Start attempting the skill as soon as you understand enough to find the first mistakes. Notice which mistakes you make. Expect about five to seven of the hundreds possible.
- Give yourself a messy problem instead of the usual practice set. Notice whether the method or order was wrong, which is a declarative gap. Notice whether the right method was done clumsily, which is a procedural gap.
- After each attempt, ask what happened, how it felt and why, what rule that suggests, and what changes next time. Notice the failed attempt turning into one specific question.
- Have an observer watch you. Notice any habit carried in from another skill that you could not see yourself.
- Change the context, the challenge type, or the time pressure on purpose. Notice whether you judge better when and why to use each move.
Related pages
- Interleaving Table: retrieval methods split by knowledge type; this page supplies the type variable
- Spaced Interleaved Retrieval: the retrieval system that takes the type variable
- Interleaving for Complex Problem Solving: the declarative-bottleneck diagnosis applied: familiar drills, collapse in context
- Knowledge Mastery From Recognition to Usable Knowledge: grades the declarative side
- Rapid Skill Acquisition: theory-to-practice pacing: working understanding, then the attempt
Open questions
- How should informed-strategy instruction that does teach the when and why be treated, given this vault’s subset stance?
Sources
- Anderson, J. R. (1982/1983). Acquisition of cognitive skill / The Architecture of Cognition. Declarative versus procedural stores; compilation can lose verbal access.
- Ryle, G. (1949). The Concept of Mind. Knowing-that and knowing-how.
- Paris, S. G., Lipson, M. Y., & Wixson, K. K. (1983). Becoming a strategic reader. Contemporary Educational Psychology. Declarative (what), procedural (how), conditional (when/why).
- Paris, S. G., & Jacobs, J. E. (1984). The benefits of informed instruction for children’s reading awareness and comprehension skills. Child Development. Strategy instruction that treats the when/why as teachable: the bound on this page’s subset stance.
- Shea, J. B., & Morgan, R. L. (1979). Contextual interference effects on the acquisition, retention, and transfer of a motor skill. Journal of Experimental Psychology: Human Learning and Memory. Varied practice grows discrimination.
- Taylor, K., & Rohrer, D. (2010). The effects of interleaved practice. Applied Cognitive Psychology.
- Rohrer, D., Dedrick, R. F., & Stershic, S. (2015). Interleaved practice improves mathematics learning. Journal of Educational Psychology. Familiar blocked drills, collapse on mixed transfer.
- Driskell, J. E., Copper, C., & Moran, A. (1994). Does mental practice enhance performance? Journal of Applied Psychology. Mental practice can move procedure a little.