1. The Question
Can AI do anything without data?
Most AI systems today assume one thing:
👉 Data comes first
But in many real-world situations—especially in healthcare—this assumption does not hold.
- Patients arrive with incomplete information
- Symptoms are noisy and ambiguous
- Ground truth is unknown at the moment of decision
And yet, decisions must be made.
So the real question becomes:
👉 How can AI make decisions when data does not yet exist?
2. The Limitation of Conventional AI
Traditional AI follows this structure:
Data → Training → Inference
This leads to several constraints:
- AI cannot function without sufficient data
- It depends on labeled datasets
- It fails in cold start situations
In other words:
👉 No data = No decision
But in domains like medical triage, this is unacceptable.
You cannot wait for data.
You must act under uncertainty.
3. A Shift in Perspective
The core assumption must change.
AI is not fundamentally a prediction system.
👉 AI is a Decision System
Instead of asking:
- “Do we have enough data to predict?”
We ask:
- “How can we structure decisions under uncertainty?”
This shift changes everything.
4. The Approach
To address this problem, we combine three components:
- Simulation
- Decision Trace Model
- Multi-Agent
These are not independent techniques.
They form a connected process that enables decision-making without prior data.
4.1 Why These Three Must Be Combined
The challenge is not just making decisions.
It is:
👉 How to start, observe, and improve decisions without data
Step 1: Simulation — Creating the Initial Form
When no data exists, we cannot begin with learning.
Instead, we create a hypothetical environment:
- Virtual patients
- Defined symptom patterns
- Assumed progression models
The purpose of simulation is not accuracy.
👉 It is to make decisions run for the first time
Simulation creates:
👉 The initial structure of decision-making
Step 2: Real-World Operation — Introducing Reality
Once deployed:
- Real patients arrive
- AI makes decisions
- Doctors intervene
- Outcomes are observed
Now we obtain something new:
👉 Real logs
Step 3: Decision Trace Model — Identifying the Gap
Simulation-based decisions will always differ from reality.
The key is not avoiding the gap, but understanding it.
Decision Trace Model decomposes decisions into:
- Event
- Signal
- Decision
- Boundary
- Human
- Log
This allows us to see:
👉 Where did the decision go wrong?
👉 Which assumption failed?
Step 4: Multi-Agent — Enabling Targeted Improvement
Real-world decisions are not singular.
They involve multiple perspectives:
- Symptom interpretation
- Risk assessment
- Prioritization
By distributing these into agents:
👉 We can isolate which part caused the deviation
Instead of retraining everything, we can:
👉 Fix specific components of the decision structure
■ What Emerges from This Combination
When these three are integrated, a new loop appears:
- Simulation creates the initial form of decision-making
- Real-world execution generates logs
- Decision Trace identifies gaps
- Multi-Agent enables targeted correction
And this leads to:
👉
Shape decisions through simulation,
detect distortions through real data,
and refine the decision structure based on those distortions
■ Why This Matters
The key is this:
We do not assume data exists at the beginning.
What we need is not:
- Perfect models
- Large datasets
But:
👉 A structure that can start decisions, record them, and improve them
Only then can meaningful data emerge.
5. Use Case: Medical Triage
In emergency departments, decisions must be made immediately:
- Which patient should be prioritized?
- How urgent is the condition?
- What test should be performed first?
The critical point is:
👉 There is no correct answer at the moment of decision
■ Decision Trace Flow
↓
Signal: Symptoms & vitals (noisy, incomplete)
↓
Decision: Triage level assignment
↓
Boundary: Escalate to human if high risk
↓
Human: Doctor makes final decision
↓
Log: Diagnosis and outcome recorded
■ Role of Simulation
- Test triage decisions with virtual patients
- Record decision outcomes
- Compare with real-world cases
■ What Happens in Improvement
Example:
- AI predicts: Medium risk
- Actual outcome: Critical condition
👉 There is a gap
Instead of retraining blindly, we analyze:
- Was the signal interpretation wrong?
- Was the risk threshold too low?
- Should escalation have happened earlier?
Then we adjust:
- Rules
- Boundaries
- Agent responsibilities
👉 Improvement is not about model retraining
👉 It is about refining the decision structure
6. The Essence
The key insight is:
👉 Data is not the starting point
Traditional approach:
Data → Learning → Inference
This approach:
Decision → Execution → Log → Data
Data is not something we begin with.
👉 It is something that emerges from decisions
More precisely:
- Decisions generate actions
- Actions produce outcomes
- Outcomes are recorded as logs
- Logs accumulate into data
👉 Data is the byproduct of structured decision-making
7. Conclusion
In uncertain domains like healthcare:
- Inputs are unstable
- Ground truth is delayed
- Data does not exist upfront
And yet, decisions must be made.
That is why we need:
- Simulation
- Decision Trace Model
- Multi-Agent
These are not tools for prediction.
They are components of a decision-making system.
■ Final Insight
AI does not run on data.
👉 AI runs on decisions—and data emerges from them.

AIシステム設計・意思決定構造の設計を専門としています。
Ontology・DSL・Behavior Treeによる判断の外部化、マルチエージェント構築に取り組んでいます。
Specialized in AI system design and decision-making architecture.
Focused on externalizing decision logic using Ontology, DSL, and Behavior Trees, and building multi-agent systems.
