Chapter 5 explores the CERIC element of Reasoning, providing a structured approach to analyzing reasoning in research articles. It distinguishes reasoning from evidence, highlights logical flow, and identifies gaps in argumentation. This chapter begins by defining reasoning and its significance, then examines various types and strategies used across disciplines. To build a foundational understanding, it first illustrates reasoning with everyday examples – such as exercising for mental health – before connecting these to the Toulmin et al. (1984) model, demonstrating how Claims, Evidence, Reasons, Support, Uncertainties, and Limitations function together. Through real-world scenarios in fields such as healthcare diagnostics and climate science, this chapter clarifies deductive, inductive, and abductive approaches, emphasizing their roles in different research contexts. Additionally, this chapter discusses how evidence, models, accuracy, precision, and flexibility interact with reasoning, underscoring the importance of transparent and well-structured logic in scientific discourse. It concludes with examples of reasoning styles from diverse research articles, reinforcing logical and analytical thinking in advancing scientific knowledge.