diff --git a/TODO.md b/TODO.md
index 11da748..f15156f 100644
--- a/TODO.md
+++ b/TODO.md
@@ -6,10 +6,7 @@
 
 # concept
 
-`conceptFromEntities` -- 构造 immutable 的 `Concept`
-`conceptFromAttributes` -- 构造 immutable 的 `Concept`
-`conceptFromEntity` -- 构造 immutable 的 `Concept` -- 有更好的名字吗？
-`conceptFromAttribute` -- 构造 immutable 的 `Concept` -- 有更好的名字吗？
+`conceptFromAttributes`
 
 # context
 
diff --git a/src/concept/conceptFromAttributes.ts b/src/concept/conceptFromAttributes.ts
new file mode 100644
index 0000000..e69de29
diff --git a/src/concept/conceptFromEntities.ts b/src/concept/conceptFromEntities.ts
new file mode 100644
index 0000000..af60f11
--- /dev/null
+++ b/src/concept/conceptFromEntities.ts
@@ -0,0 +1,23 @@
+import {
+  commonAttributes,
+  commonEntities,
+  type Context,
+  type Entity,
+} from "../context/index.js"
+import type { Concept } from "./Concept.js"
+
+export function conceptFromEntities(
+  context: Context,
+  entities: ReadonlySet<Entity> | ReadonlyArray<Entity>,
+): Concept {
+  entities = new Set(entities)
+
+  const intent = commonAttributes(context, entities)
+  const extent = commonEntities(context, intent)
+
+  return {
+    context,
+    extent,
+    intent,
+  }
+}
diff --git a/src/concept/index.ts b/src/concept/index.ts
index 36ec376..5f67145 100644
--- a/src/concept/index.ts
+++ b/src/concept/index.ts
@@ -1,5 +1,7 @@
 export * from "./closureAttributes.js"
 export * from "./closureEntities.js"
 export * from "./Concept.js"
+export * from "./conceptFromAttributes.js"
+export * from "./conceptFromEntities.js"
 export * from "./isExtent.js"
 export * from "./isIntent.js"