A Formal Comparison Between Chain-of-Thought and Latent Thought
- URL: http://arxiv.org/abs/2509.25239v1
- Date: Thu, 25 Sep 2025 11:27:52 GMT
- Title: A Formal Comparison Between Chain-of-Thought and Latent Thought
- Abstract summary: Chain-of-Thought (CoT) elicits reasoning in large language models by explicitly generating intermediate steps in natural language.<n>Latent Thought in looped models operates directly in the continuous latent space, enabling computation beyond discrete linguistic representations.
- Score: 32.84174396586435
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: Chain-of-Thought (CoT) elicits reasoning in large language models by explicitly generating intermediate steps in natural language. In contrast, Latent Thought in looped models operates directly in the continuous latent space, enabling computation beyond discrete linguistic representations. While both approaches exploit iterative computation, their comparative capabilities remain underexplored. In this work, we present a formal analysis showing that Latent Thought in Looped Transformers enables parallel computation, which is more efficient than the inherently sequential process of CoT. In contrast, CoT leverages stochastic decoding to approximate solutions to problems where exact computation is intractable. These separations suggest the tasks for which depth-driven recursion is more suitable, thereby offering practical guidance for choosing between reasoning paradigms. Code is available at https://github.com/kevin671/cot-vs-loop.
Related papers
- Think Wider: Mitigating Latent Rank Collapse in Implicit Chain-of-Thought Reasoning [3.216436532980238]
Chain-of-thought (CoT) reasoning improves the reasoning ability of large language models by introducing intermediate computation.<n>However, explicit rationales increase decoding length, latency, and context cost.<n>Implicit CoT offers a more efficient alternative by moving intermediate reasoning into continuous latent states.
arXiv Detail & Related papers (2026-09-07T12:18:51Z) - Think Deep, Speak Once: Relit, A Recursive Latent Implicit Transformer Framework [2.007262412327553]
We introduce ReLIT, a hybrid framework for deep, semantically grounded implicit reasoning.<n>We show that ReLIT can be scaled efficiently through recurrent depth rather than parameter width.<n>These results demonstrate that reasoning capability can be scaled efficiently through recurrent depth rather than parameter width.
arXiv Detail & Related papers (2026-08-08T12:50:51Z) - Is Code Better Than Language for Algorithmic Reasoning [58.86873062890482]
We show that for tool-augmented language models, comparing natural-language reasoning with code-execution pipelines is difficult because the comparison changes both the intermediate representation and the execution mechanism.<n>We separate these factors with an intermediate intervention: the model expresses its reasoning as executable code, and the language model simulates that code in context to produce an answer.<n>We observe that the intermediate intervention is not meaningfully different from natural-language reasoning (+0.15pp)
arXiv Detail & Related papers (2026-06-14T04:17:21Z) - Generative Recursive Reasoning [67.22973831501257]
Generative Recursive reAsoning Models (GRAM) is a framework that turns latent reasoning into probabilistic multi-trajectory.<n>GRAM supports conditional reasoning via $p_(y mid x)$ and, with fixed or absent inputs, unconditional generation via $p_(x)$.
arXiv Detail & Related papers (2026-05-19T05:20:56Z) - Latent Chain-of-Thought as Planning: Decoupling Reasoning from Verbalization [9.193078163792427]
Chain-of-Thought (CoT) empowers Large Language Models (LLMs) to tackle complex problems.<n>Recent latent reasoning approaches attempt to optimize efficiency by performing reasoning within continuous hidden states.<n>We introduce PLaT, a framework that reformulates latent reasoning as planning by fundamentally decouple reasoning from verbalization.
arXiv Detail & Related papers (2026-01-29T07:38:18Z) - Neural Chain-of-Thought Search: Searching the Optimal Reasoning Path to Enhance Large Language Models [61.55758048622473]
We introduce Neural Chain-of-Thought Search (NCoTS), a framework that reformulates reasoning as a dynamic search for the optimal thinking strategy.<n>By quantitatively characterizing the solution space, we reveal the existence of sparse superior reasoning paths that are simultaneously more accurate and concise than standard outputs.
arXiv Detail & Related papers (2026-01-16T14:38:18Z) - Dual-Density Inference for Efficient Language Model Reasoning [26.002819535382855]
We present Denser: underlineDual-dunderlineensity infunderlineerence, a novel framework that optimize information density separately for reasoning and answering phases.<n>Our framework implements this through three components: a query processing module that analyzes input problems, a high-density compressed reasoning mechanism for efficient intermediate computations, and an answer generation component that translates compressed reasoning into human-readable solutions.
arXiv Detail & Related papers (2025-12-17T12:04:05Z) - Latent Chain-of-Thought? Decoding the Depth-Recurrent Transformer [0.8738725605667471]
Chain-of-thought (CoT) reasoning has enabled transformer-based language models to excel at complex mathematics and multi-step planning.<n>In standard decoder-only architectures, these reasoning steps are externalized in natural language, improving interpretability at the cost of efficiency.<n>We investigate whether such reasoning structures emerge in Huginn-3.5B, a depth-recurrent Transformer that reuses layers at inference time without increasing parameter count.
arXiv Detail & Related papers (2025-07-02T23:35:21Z) - Theorem-of-Thought: A Multi-Agent Framework for Abductive, Deductive, and Inductive Reasoning in Language Models [2.172419551358714]
Large language models (LLMs) have shown strong performance across natural language reasoning tasks, yet their reasoning processes remain brittle and difficult to interpret.<n>We introduce Theorem-of-Thought (ToTh), a novel framework that models reasoning as collaboration among three parallel agents.<n> Experiments on symbolic (WebOfLies) and numerical (MultiArithm) reasoning benchmarks show that ToTh consistently outperforms CoT, Self-Consistency, and CoT-Decoding.
arXiv Detail & Related papers (2025-06-08T12:28:38Z) - To CoT or To Loop? A Formal Comparison Between Chain-of-Thought and Looped Transformers [32.01426831450348]
Chain-of-Thought (CoT) and Looped Transformers have been shown to empirically improve performance on reasoning tasks.<n>We provide a formal analysis of their respective strengths and limitations.
arXiv Detail & Related papers (2025-05-25T17:49:37Z) - Soft Thinking: Unlocking the Reasoning Potential of LLMs in Continuous Concept Space [62.54887038032942]
We introduce Soft Thinking, a training-free method that emulates human-like "soft" reasoning by generating soft, abstract concept tokens.<n>These concept tokens are created by the probability-weighted mixture of token embeddings, which form the continuous concept space.<n>In essence, each generated concept token encapsulates multiple meanings from related discrete tokens, implicitly exploring various reasoning paths to converge.
arXiv Detail & Related papers (2025-05-21T17:29:15Z) - Reasoning by Superposition: A Theoretical Perspective on Chain of Continuous Thought [56.71873693264532]
We prove that a two-layer transformer with $D$ steps of continuous CoTs can solve the directed graph reachability problem.<n>In our construction, each continuous thought vector is a superposition state that encodes multiple search frontiers simultaneously.
arXiv Detail & Related papers (2025-05-18T18:36:53Z) - Reasoning with Latent Thoughts: On the Power of Looped Transformers [52.84192961524481]
We show that for many synthetic reasoning problems, a $k$-layer transformer looped $L$ times nearly matches the performance of a $kL$-layer non-looped model.<n>Our empirical analysis reveals an intriguing phenomenon: looped and non-looped models exhibit scaling behavior that depends on their effective depth.
arXiv Detail & Related papers (2025-02-24T18:49:05Z) - FLARE: Faithful Logic-Aided Reasoning and Exploration [47.46564769245296]
We introduce a novel approach for traversing the problem space using task decompositions.<n>We use the Large Language Models to plan a solution, soft-formalise the query into facts and predicates using a logic programming code.<n>Our method allows us to compute the faithfulness of the reasoning process w.r.t. the generated code and analyse the steps of the multi-hop search without relying on external solvers.
arXiv Detail & Related papers (2024-10-14T19:39:11Z) - Generating Chain-of-Thoughts with a Pairwise-Comparison Approach to Searching for the Most Promising Intermediate Thought [70.30423016640749]
Chain-of-thoughts (CoT) methods were proposed to guide large language models to reason step-by-step, enabling problem solving from simple to complex.
The evaluation from the large language model (LLMs) is typically noisy and unreliable, potentially misleading the generation process in selecting promising intermediate thoughts.
In this paper, motivated by Vapnik's principle, we use pairwise-comparison evaluation instead of point-wise scoring to search for promising intermediate thoughts.
arXiv Detail & Related papers (2024-02-10T09:51:03Z) - Object Representations as Fixed Points: Training Iterative Refinement
Algorithms with Implicit Differentiation [88.14365009076907]
Iterative refinement is a useful paradigm for representation learning.
We develop an implicit differentiation approach that improves the stability and tractability of training.
arXiv Detail & Related papers (2022-07-02T10:00:35Z) - Consistency of a Recurrent Language Model With Respect to Incomplete
Decoding [67.54760086239514]
We study the issue of receiving infinite-length sequences from a recurrent language model.
We propose two remedies which address inconsistency: consistent variants of top-k and nucleus sampling, and a self-terminating recurrent language model.
arXiv Detail & Related papers (2020-02-06T19:56:15Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.