diff --git a/README.md b/README.md
index 25f1b85..af01744 100644
--- a/README.md
+++ b/README.md
@@ -88,7 +88,7 @@ Only available to deriving classes. Trigger all listeners of a particular event.
 ```ts
 emit(
   event: string,
-  thisArg: any,
+  thisArg?: any,
   ...args: any
 ): Promise<any>
 ```
diff --git a/src/index.ts b/src/index.ts
index 4d98ba3..a8313c8 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -34,7 +34,7 @@ export default abstract class Houk {
 	 */
 	protected async emit(
 		event: string,
-		thisArg: any,
+		thisArg?: any,
 		...args: any
 	): Promise<any> {
 		const listeners = this.getListeners(event);