Building a Thinking Model from a Non-Thinking Model Using Chain-of-Thought

Mantu KumarMantu Kumar
2 min read

Not every AI model is a natural "thinker." Many large language models are excellent at producing fluent text, but they're really just pattern matchers—predicting the next word based on training data, not genuinely reasoning things through.


1. What is a "Non-Thinking" Model?

A non-thinking model generates answers by recognizing patterns, not by following logical steps. It might give convincing responses, but when a problem requires logic, math, or multi-step reasoning, it can easily go wrong.

Example:

Q: I have 3 apples and eat 1. How many are left? Non-thinking answer: "You have apples left." (vague, no real reasoning)


2. Enter Chain-of-Thought

Chain-of-Thought (CoT) prompting is a way of telling the model to think step-by-step before giving the final answer. This makes the reasoning process visible—just like a person writing out their working.

Example with CoT:

Q: I have 3 apples and eat 1. How many are left? Model thinking: "Start with 3. Eating 1 leaves 2. Final answer: 2." Answer: 2


3. Why It Works

Even "non-thinking" models have seen reasoning patterns during training. CoT activates these patterns by:

  • Breaking problems into smaller steps.

  • Reducing random guessing.

  • Making reasoning explicit, which improves accuracy.


4. How to Use It

  1. Be explicit: Tell the model, "Think step-by-step."

  2. Add self-checks: Ask it to verify the result.

  3. Hide reasoning if needed: You can keep the thought process internal but only show the final answer to users.

Example prompt:

Q: A train leaves at 2 PM and arrives at 5 PM. How long was the trip?  
Think step-by-step, then give the final answer.

5. From Guessing to "Thinking"

With CoT , a non-thinking model becomes a pseudo-thinker:

  • It's not conscious.

  • But it follows a process that mimics human reasoning.

  • Fine-tuning can make this process even more reliable.


Final Thoughts

Chain-of-Thought doesn't give AI real understanding, but it's the simplest way to turn a quick guesser into a methodical problem solver—no retraining, just better prompts and a habit of reasoning out loud.

0
Subscribe to my newsletter

Read articles from Mantu Kumar directly inside your inbox. Subscribe to the newsletter, and don't miss out.

Written by

Mantu Kumar
Mantu Kumar