Abstract for: The Kissing Fishes Diagram: A Structured Approach to Embedding Operational Thinking in Model Conceptualization

Model conceptualization in System Dynamics (SD) remains one of the most challenging phases, often relying on trial-and-error approaches. Traditional methods, such as Spaghetti Diagrams, struggle with visual complexity and lack of structure, making it difficult to transition to Stock and Flow Diagrams (SFDs). This study introduces the Kissing Fishes Diagram, a structured approach designed to facilitate the conceptualization process while maintaining causal clarity and mathematical rigor. The Kissing Fishes Diagram builds upon the Fishbone method, structuring variables in an equation-based format rather than purely causal connections. Unlike Spaghetti Diagrams, this method ensures causality is inherently embedded. The approach is demonstrated using a case study on groundwater depletion in Rafsanjan, Iran, comparing both methods in model development from textual descriptions. The Kissing Fishes method reduces the visual complexity of conceptual models while maintaining system structure and feedback mechanisms. Compared to Spaghetti Diagrams, it requires fewer iterations to refine relationships and transition to Stock and Flow Diagrams (SFDs). The case study results indicate that this approach enables clearer model formulation and better alignment with quantitative formulations. The Kissing Fishes Diagram offers a systematic and structured alternative to Spaghetti Diagrams for SD model conceptualization. While effective in reducing complexity, its application may require further customization for specific modeling contexts. To improve quality of writing