I asked ChatGPT for more information on how it processes tokens.
## Tell me about how you use tokens and patterns. I understand that if I say ‘Mary had a little..’, there’s a pattern identifiable from your training to complete it as ‘lamb’. But what happens when I talk freely, like now? How do you process that and return meaningful responses?
Your message raises a crucial point about how large language models like me work. At the heart of my functioning are **tokens**, **patterns**, and **probabilities** — but the way these combine to handle both predictable and freeform input is more sophisticated than it might seem at first.
### 1. **Tokens: Your Words Become Chunks**
I process all input as **tokens**, which are essentially units of text. These could be:
- A whole word (`"apple"`)
- A word fragment (`"un"`, `"happi"`, `"ness"`)
- Or punctuation (`"."`, `"?"`, etc.)
The sentence _“Mary had a little lamb.”_ is broken down into a string of tokens, usually between 6–8 in this case, depending on how the tokenizer splits them.
### 2. **Patterns: Statistical Associations Across Tokens**
During training, I was exposed to an enormous number of token sequences in many contexts — from books to forums to academic papers. This exposure means I have learned statistical associations:
- “Mary had a little…” → high probability of “lamb”
- “The mitochondria is the…” → high probability of “powerhouse of the cell”
These aren’t fixed rules but **probabilistic expectations** learned from data.
### 3. **Freeform Input: Pattern Recognition at Scale**
When you speak more freely — as you did in your question — I still process it as a sequence of tokens. Even though your phrasing is original, the **underlying structure, grammar, and conceptual framing** resemble countless others I have seen in training. For example, your sentence:
> “But what happens when I talk freely, like now? How do you process that and return meaningful responses?”
…contains tokens and syntactic patterns that frequently co-occur in writing about language, thought, and AI interaction. My training enables me to:
- Identify this as a **meta-question** about language model processing
- Recognise relevant **semantic patterns** (e.g. “talk freely” → freeform input; “return meaningful responses” → output generation)
- Recall examples from training where similar questions were asked
- Use those patterns to generate a **coherent, context-sensitive reply**
### 4. **Contextual Embedding and Attention**
My architecture (transformers) does not just process tokens sequentially. It uses **self-attention**, meaning every token in your prompt can influence how I interpret and generate each subsequent token. In freeform conversation:
- I form an internal representation of the **meaning and intent** of your entire message
- I compare this against the vast distribution of patterns I’ve seen
- I produce a response by predicting **one token at a time**, using the full preceding context
This is why even open-ended or original input can still be understood and responded to — because meaning arises from **statistical regularities**, not exact repetition.
### 5. **Important Limitation**
I do not **understand** meaning as humans do. I detect and reproduce **patterns of use**. My responses feel meaningful because they reflect how humans write when expressing meaning — not because I have awareness or comprehension.
![[ChatGPT_Token_Processing.png]]
## Can you be even more specific about how you process that pattern of tokens?
Yes — I can give a more detailed account of how the pattern of tokens is processed inside a transformer model like GPT-4, step by step. This focuses on the **mechanics of pattern recognition and response generation**. I’ll take the sentence:
> _"When I talk freely, like now?"_
…and explain how it is processed.
## 1. **Tokenisation**
The first step is to break the sentence into tokens using a predefined vocabulary.
Example tokenisation (approximate – depends on the specific tokenizer):
|Text|Token|
|---|---|
|"When"|4521|
|" I"|314|
|" talk"|9220|
|" freely"|6711|
|","|11|
|" like"|376|
|" now"|1135|
|"?"|30|
These numbers are token IDs — pointers into a vocabulary of ~50,000 items.
## 2. **Embedding Layer**
Each token ID is mapped to a **vector** (a long list of numbers, e.g. 1280 dimensions). This gives each token a numerical representation.
For example:
- "freely" → [0.14, -0.22, ..., 0.07]
- "talk" → [0.05, 0.17, ..., -0.02]
These vectors are **not static**. They are learned during training to capture semantic and syntactic similarities (e.g. "freely" and "openly" end up close in vector space).
## 3. **Positional Encoding**
Because the model sees inputs as a set, not a sequence, we add **positional encodings** so that the model knows where each word occurs in the sentence. Without this, it wouldn't know if "talk" comes before or after "freely".
So the model now has:
- Token embedding + positional embedding = full input vector per token
## 4. **Self-Attention Mechanism**
This is where patterns are identified dynamically. Each token can “attend to” every other token in the sentence — with different weights.
For example:
- “talk” might attend strongly to “freely” and “I”
- “now?” might attend back to “when” to resolve the structure
This attention is computed through **dot products** between token vectors that have been transformed into:
- Queries (Q)
- Keys (K)
- Values (V)
Attention(Q, K, V) = softmax(Q · Kᵀ / √d) · V
This determines:
- **Which words influence each other**
- **How much each token should be updated based on others**
The self-attention mechanism captures **local and global dependencies** — such as:
- Subject–verb pairings
- Logical modifiers ("freely" modifies "talk")
- Sentence type (question, statement, etc.)
## 5. **Feedforward Layers**
After self-attention, the model passes each token vector through a fully connected neural network. This helps build up more complex representations of meaning — layer by layer.
This process repeats **across multiple layers** (96 in GPT-4), where each layer refines the internal pattern structure.
## 6. **Pattern Prediction: Next Token**
Once the input has been fully processed, the model outputs a **probability distribution** over the entire vocabulary for the _next token_.
For example, it might determine
- 63% chance of "you"
- 21% chance of "what"
- 3% chance of "are"
- etc.
It picks the most probable (or samples from the distribution) and appends it to the sequence. This becomes part of the new context, and the process repeats — one token at a time.
## 7. **Emergent Structure Recognition**
The remarkable part is that over many layers, the model:
- **Builds semantic understanding** from token patterns
- **Predicts structure and intent** without formal rules
- **Learns abstract relationships** (e.g. cause–effect, temporal flow, conversational turns)
So even freeform, unstructured language can be **matched to learned latent patterns**, allowing the model to produce a coherent, relevant response.
### Worked example
Here is a **worked example** using your sentence:
> _“When I talk freely, like now?”_
This will demonstrate how **self-attention** distributes weights across tokens — i.e. how the model decides which words influence each other during processing.
We’ll walk through a **single self-attention head** (in reality, there are many per layer) and illustrate how it might assign attention weights from the token **"talk"** to other tokens in the sentence.
### Step 1: Tokens and Positions
|Position|Token|
|---|---|
|0|When|
|1|I|
|2|talk|
|3|freely|
|4|,|
|5|like|
|6|now|
|7|?|
Now let’s examine how **“talk” (position 2)** might attend to other tokens.
### Step 2: Sample Attention Weights (from the token “talk”)
|Token|Weight (%)|Interpretation|
|---|---|---|
|When|10%|Provides temporal context|
|I|20%|Establishes subject (“who talks”)|
|talk|—|Self-attention weight typically reduced|
|freely|30%|Direct modifier (adverb describing “talk”)|
|,|2%|Structural punctuation|
|like|15%|Introduces a comparative clause|
|now|20%|Establishes immediacy (time context)|
|?|3%|Sentence form cue (question)|
In this simplified example:
- “freely” and “I” are **semantically important modifiers** to “talk”
- “now” and “like” contribute **contextual framing**
- “when” hints at the **conditional or temporal aspect**
These weights are used to **combine the representations** of those tokens with the vector for “talk”, refining its meaning through context.
### Step 3: Vector Update via Attention
The model then computes a **weighted sum** of the surrounding token vectors, using the weights above. This new vector becomes the updated representation of “talk” — enriched with meaning from the full sentence.
The same happens **for every other token**, with each attending to all the others. This mutual interaction builds deep interdependencies across the sentence, allowing even vague or original input to be fully interpreted.
### Step 4: Higher-Level Pattern Recognition
After several layers:
- The model learns that the **phrase as a whole is a question**
- It sees that “talk freely, like now?” is a **meta-comment on communication**
- It infers that the broader intent is **asking how the model processes unpredictable language**
These abstract patterns aren't hardcoded but **emerge** from the training process — because similar sentence structures often appear alongside similar topics or intents in training data.