Conceptually, LLM reasoning is a linear process, "confined to token-level, left-to-right decision-making processes during inference." This means that when confronted with complex or ambiguous phrasing, LLMs must simply plow through the text in linear order in a single pass. Humans, on the other hand, when confronted with text that seems contradictory or ambiguous, will reread it multiple times and leverage external world knowledge to assess the true intended meaning of the text. The inability of LLMs to re-read passages to reason over ambiguous meaning can be especially problematic in the domain of news coverage in which turns of phrase or space constraints can yield more complex formulations of prose.

For example, take this passage from a Wall Street Journal article last week:

Threads will be compatible with ActivityPub, a decentralized social-networking protocol—the same one used by Mastodon. What does that mean? It is “decentralized” because hosting of accounts, including people’s followers, can be done on independent servers, rather than those operated privately by a single company. This is the way Meta currently runs Facebook and Instagram.

Depending on how one reads the passage, it is either entirely clear or seemingly contradictory regarding whether Meta operates Facebook and Instagram as centralized or decentralized platforms. The third sentence is meant to follow from the last clause of the second sentence, but grammatically would appear to follow from the first. In other words, "It is 'decentralized'" connects to "This is the way Meta…" is the typical reasoning chain implied by this kind of grammatical construction, while the actual meaning lies in the last clause "operated privately by a single company."

To put another way, if the passage is read quickly, it may read as "It is 'decentralized' because hosting of accounts, including people's followers, can be done on independent servers … This is the way Meta currently runs Facebook and Instagram." instead of the intended reading of "operated privately by a single company. This is the way Meta currently runs Facebook and Instagram."

Humans that read the passage too quickly and follow the generic grammatical construct leading to the former interpretation will typically recognize a seeming contradiction in the passage and reread it automatically (potentially without realizing they are doing so) to clarify the intended meaning. LLMs, on the other hand, cannot do so.

What happens if we ask ChatGPT to parse this sentence?

We'll use the following prompt:

Based on the following text, is Instagram decentralized? "Threads will be compatible with ActivityPub, a decentralized social-networking protocol—the same one used by Mastodon. What does that mean? It is 'decentralized' because hosting of accounts, including people's followers, can be done on independent servers, rather than those operated privately by a single company. This is the way Meta currently runs Facebook and Instagram."

And here are the responses ChatGPT provided when we posed this prompt to it repeatedly:

• Based on the provided text, it states that Meta, the parent company of Facebook and Instagram, currently runs Facebook and Instagram in a decentralized manner, similar to ActivityPub's decentralized social-networking protocol. However, the text does not explicitly mention that Instagram specifically uses ActivityPub. It suggests that Instagram follows a decentralized hosting model like ActivityPub, but it does not confirm whether Instagram integrates the ActivityPub protocol itself.
• Based on the provided text, it states that Meta currently runs Facebook and Instagram in a decentralized manner. It suggests that the hosting of accounts, including people's followers, can be done on independent servers rather than being operated privately by a single company. This decentralized hosting model aligns with the concept of ActivityPub, a decentralized social-networking protocol used by Mastodon. However, the text does not explicitly state that Instagram is fully decentralized. It indicates that Meta operates Instagram in a decentralized way similar to ActivityPub, but it does not confirm the extent to which Instagram implements the ActivityPub protocol or if it is fully decentralized in all aspects.
• Based on the provided text, it suggests that Meta, the parent company of Facebook and Instagram, currently runs both platforms, including Instagram, in a decentralized manner. The text states that hosting of accounts and followers can be done on independent servers rather than being operated privately by a single company. This aligns with the concept of decentralization, similar to the approach taken by ActivityPub, a decentralized social-networking protocol used by Mastodon. However, without further information, it cannot be conclusively stated whether Instagram is fully decentralized in all aspects. The text implies that Meta follows a decentralized hosting model for both Facebook and Instagram, but the specific implementation and extent of decentralization within Instagram are not explicitly mentioned.
• Based on the provided text, it indicates that Meta, the parent company of Facebook and Instagram, currently operates both platforms, including Instagram, in a decentralized manner. The text specifically mentions that hosting of accounts and followers can be done on independent servers instead of being privately operated by a single company. This aligns with the concept of decentralization, which is also a characteristic of the ActivityPub protocol used by Mastodon. Therefore, based on the information given, Instagram can be considered decentralized, as it follows the decentralized hosting model described in the text.
• Based on the provided text, it suggests that Meta, the parent company of Facebook and Instagram, currently runs both platforms, including Instagram, in a decentralized manner. The text states that hosting of accounts and followers can be done on independent servers, indicating a decentralized hosting approach. It specifically mentions that Meta runs Facebook and Instagram in this manner. Therefore, based on the information given, it can be inferred that Instagram is decentralized, following the same decentralized hosting model used by Meta for both platforms.

Despite repeating our prompt five times, in all five cases ChatGPT interpreted the passage as indicating that Meta's Facebook and Instagram use a decentralized model – the straightforward linear grammatical interpretation of the passage. Unlike human readers, it is unable to recognize a contradiction with its understanding of Meta's operations from its knowledge store and reread the text to identify possible alternative interpretations.

Domains like news tend to prize turns of phrase and creative prose, posing an especially unique challenge to the application of LLMs.