> ## Documentation Index
> Fetch the complete documentation index at: https://docs.chief.bot/llms.txt
> Use this file to discover all available pages before exploring further.
# Concept Timelines
> When you open a Concept, its details panel shows a timeline of the citations the Concept was built from.
## What a Concept Timeline is
When you open a [Concept](/help/concepts/what-are-concepts), its details panel shows a **timeline of the [citations](/help/chatting-with-chief/understanding-sources-citations-in-answers) the Concept was built from**. Each entry is a source file and the passages (chunks) Chief drew from it, listed with the passage's date. The timeline is your audit trail: it lets you see, in order, [exactly which evidence across your Library supports a theme](/help/how-chief-works-magic-under-the-hood/how-chief-creates-concepts) — so a Concept is never a black box.
## Open a Concept's timeline
1. Go to [the **Concepts** page](/help/concepts/navigating-the-concepts-view-viewing-concept-details) in your Library.
2. Click a Concept card to open its details in the side panel.
3. Below the summary, find the line **This Concept is built from N citations**. The citation timeline appears beneath it.
## Read the timeline
1. Each source file appears as an entry, connected down the panel so you can follow the sequence.
2. Each entry shows the citation name, a link reading **from \{file name}** back to the source file, and the passage's date.
3. Click a passage to expand its full text; click again to collapse it back to a few lines.
4. When an entry has several passages, click the **+ N more sources** control to reveal the rest.
ℹ️ **Good to Know:** Click **from \{file name}** on any citation to open the underlying file and read the passage in its full context.
## When some citations are hidden
If you opened the Concept from inside a filtered view (such as a [Collection](/help/collections/what-are-collections)), the timeline shows only citations from files within that view. A note tells you how many additional citations are hidden because they fall outside your data view. Click **Remove filters** in that note to see the Concept's complete timeline.
🚀 **Pro-Tip:** Use the dates on the timeline to spot how a theme developed over time — whether it shows up mostly in your earliest files or keeps recurring in your most recent ones.
## Frequently asked questions
Chief is fetching the Concept's citations. This is normal; the timeline appears once loading finishes.
The citations couldn't load this time. Close and reopen the Concept, or refresh the page, to retry.
No. The Concept simply has no source passages attached yet, which is common right after you define a Concept. Give Chief time to build it and the timeline will fill in.
You're probably viewing the Concept through a filter, so citations from files outside that view are hidden. Click **Remove filters** to see every citation.