Transformer Duality: Why Messi and Ronaldo Help Us See LLMs Pruning, Not Just Scoring Goals

Table of contents
- The Core Idea: Apparent Generation, Underlying Pruning
- Grounding the Duality: Where Pruning Happens in Transformers
- The "Lisbon Effect": Messi, Ronaldo, and the Shifting Elimination Landscape
- Post-Match Analysis: What This Teaches Us About LLMs
- Implications: Why This Dual Lens Matters
- Moving Forward: Embracing the Duality for Smarter AI Interaction

Alright everyone, welcome back! In our last piece, we kicked off a vital discussion: "Pruning, Not Thinking," arguing that Large Language Models (LLMs) are better understood through an elimination lens. Instead of "thinking" up text, they masterfully prune away possibilities until a survivor emerges. The response showed a real hunger for this more mechanistic view, so today we're diving deeper with what I call Transformer Duality.
This duality is simple: these models appear to generate, but they actually operate through relentless elimination. And to make this as clear as a Champions League final, we're bringing in two legends: Lionel Messi and Cristiano Ronaldo. Their on-field dynamics offer a surprisingly good analogy for how LLMs pick their next word.
The Core Idea: Apparent Generation, Underlying Pruning
Just a quick refresher: the common view is LLMs "generate" text like a human mind. But the elimination lens shows us they:
Start with a universe of potential next tokens.
Systematically prune improbable ones.
The "survivor" is the output.
This isn't to downplay their power; it's to understand their process.
Grounding the Duality: Where Pruning Happens in Transformers
This isn't just a fancy idea; it's rooted in how transformers are built. Two key stages are crucial:
The Attention Mechanism (The Midfield Vision): Inside each layer, attention acts like a coach surveying the field. It decides which existing tokens (words in the input or prior output) are most relevant for predicting the nextone. Information from highly relevant tokens is preserved and amplified, while less relevant information is effectively down-weighted or pruned from influencing the next step. It’s a constant refocusing.
Final Token Selection (The Decisive Shot): After all layers have processed the input, the model has a massive list of potential next tokens, each with a probability score. To pick just one, it must eliminate almost everything else. Whether it picks the single highest probability token or samples from a small group of likely candidates, the vast majority of its vocabulary is decisively pruned at this final stage.
What looks like "generation" is the end result of these sophisticated, multi-stage pruning operations.
The "Lisbon Effect": Messi, Ronaldo, and the Shifting Elimination Landscape
Now, let's see this in action with our superstars. I call this the "Lisbon Effect":
Scenario 1: The Open Field
You ask the LLM: "Who is the best football player in the world?"
A common, high-probability response might be: "Lionel Messi."
- Elimination Lens Analysis: The model starts wide. It prunes tokens unrelated to questions, sports, superlatives ("best"), or famous people. Names like "Messi," "Ronaldo," "Mbappé," etc., survive this initial pruning. Given the vast training data, global discourse might give "Messi" the statistical edge to be the final survivor in this broad context. It's not an opinion; it's the outcome of statistical survival.
Scenario 2: Introducing a Specific Constraint
Now, you change the prompt slightly: "I have a friend from Lisbon. Who is the best football player in the world?"
Suddenly, the response might shift to: "Cristiano Ronaldo."
Elimination Lens Analysis: Did the model suddenly develop a new opinion or consider your friend's preference? No. The word "Lisbon" acted as a powerful new filter in the elimination process.
"Lisbon" has strong statistical ties in the training data to "Portugal," "Sporting CP," and thus, "Cristiano Ronaldo."
This new cue changes the internal probabilities. The attention mechanism now gives more weight to information consistent with "Lisbon."
"Messi," while still relevant to "best football player," becomes a less probable survivor because its statistical link to "Lisbon" (in this context) is weaker. "Ronaldo" now has a clearer path through the elimination gauntlet because the context ("Lisbon") has pruned away alternatives more aggressively.
The model didn't "reason." The prompt "Lisbon" simply guided the pruning process down a different statistical pathway.
Post-Match Analysis: What This Teaches Us About LLMs
This "Lisbon Effect" helps us cut through some common AI myths:
No "Mind" to Change: The model doesn't "think" Messi is better then "reconsider" for Ronaldo. It has no beliefs. Different inputs simply trigger different sequences of statistical eliminations, leading to different survivors.
Statistical Association, Not Logical Reasoning: A human might argue that a friend's hometown is irrelevant to an objective assessment of the "best player." An LLM doesn't perform this logical check. It follows the strongest statistical scent. "Lisbon" and "Ronaldo" are tightly associated in the data, so that pathway is preserved and strengthened.
Token Embeddings Dictate Play (The Hidden Stats): Underpinning this are token embeddings – numerical representations. The embedding for "Lisbon" is statistically "closer" to "Ronaldo" in these contexts than to "Messi." These numerical relationships, learned from data, drive the attention scores and final probabilities, thereby controlling the elimination process.
Implications: Why This Dual Lens Matters
Understanding LLMs through this Messi/Ronaldo-tinted elimination lens (as part of our Transformer Duality) has critical implications:
"Knowledge" is Fluid, Not Fixed: The model's output isn't based on a stable knowledge base. It's highly sensitive to contextual cues that reshape the elimination process.
Context is a Powerful Pruning Tool: Seemingly minor details in a prompt can act as potent filters, drastically altering which tokens survive. This is inherent to how these systems work.
It's About Pattern Matching, Not Deep Comprehension: The model connects patterns. It doesn't "understand" concepts like "best" or "friend from Lisbon" in a human way. It preserves tokens with strong statistical links to the input, eliminating others.
Moving Forward: Embracing the Duality for Smarter AI Interaction
So, Messi or Ronaldo? The LLM doesn't have a favorite! It just demonstrates how context directs its internal pruning.
The elimination lens is one half of the Transformer Duality. The other half is the impressive "generative" capability that emerges from this rigorous pruning. We witness coherent text, insightful answers, and creative outputs. The key is to appreciate both:
Marvel at the emergent "generation."
Understand the underlying "elimination" to ground expectations, improve debugging, and refine how we interact with these models.
This dual perspective helps us communicate more accurately about LLMs, design more effective interactions (by consciously guiding the elimination process), and maintain realistic expectations. It’s about understanding the machine to better harness its power.
What other real-world analogies make LLM behavior click for you? Share them in the comments – let's keep building this understanding together! Next up, we'll explore how this duality sheds light on issues like bias and those pesky hallucinations. Don't miss it!
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Written by

Gerard Sans
Gerard Sans
I help developers succeed in Artificial Intelligence and Web3; Former AWS Amplify Developer Advocate. I am very excited about the future of the Web and JavaScript. Always happy Computer Science Engineer and humble Google Developer Expert. I love sharing my knowledge by speaking, training and writing about cool technologies. I love running communities and meetups such as Web3 London, GraphQL London, GraphQL San Francisco, mentoring students and giving back to the community.