It depends on what you mean by smart.

- If you value raw observation and forensic deduction: Sherlock Holmes. He’s unmatched at extracting facts from minute physical traces, rapid reasoning, and specialized knowledge.
- If you value psychological insight and strategic manipulation: Hercule Poirot. He excels at reading character, spotting lies and motives, and orchestrating airtight endgames.

Within their own stories, each is written to be the smartest person in the room. So the “smarter” one is the one whose strengths fit the case: Holmes for physical clues, Poirot for human ones. Call it a draw.
