diff --git a/speaker.py b/speaker.py
index 4f07748..3d44df3 100644
--- a/speaker.py
+++ b/speaker.py
@@ -45,7 +45,7 @@ class Speaker(object):
     def __init__(self, username, archivist, logger, admin=0, nicknames=[],
                  reply=0.1, repeat=0.05, wakeup=False, mode=ModeFixed,
                  memory=20, mute_time=60, save_time=3600, bypass=False,
-                 filter_cids=[], max_len=50
+                 cid_whitelist=None, max_len=50
                  ):
         self.names = nicknames
         self.mute_time = mute_time
@@ -66,7 +66,7 @@ class Speaker(object):
         self.logger = logger
         self.reply = reply
         self.repeat = repeat
-        self.filter_cids = filter_cids
+        self.cid_whitelist = cid_whitelist
         self.memory = MemoryList(memory)
         self.save_time = save_time
         self.memory_timer = int(time.perf_counter())
@@ -219,7 +219,7 @@ class Speaker(object):
 
     def say(self, bot, reader, replying=None, **kwargs):
         cid = reader.cid()
-        if cid not in self.filter_cids:
+        if self.cid_whitelist is not None and cid not in self.cid_whitelist:
             return
         if self.is_mute():
             return
diff --git a/velasco.py b/velasco.py
index a5b8380..8670544 100644
--- a/velasco.py
+++ b/velasco.py
@@ -79,7 +79,7 @@ def main():
                         help='The ID of the Telegram user that manages this bot')
     parser.add_argument('-w', '--wakeup', action='store_true',
                         help='Flag that makes the bot send a first message to all chats during wake up.')
-    parser.add_argument('-f', '--filter', nargs='*', default=[], metavar='cid',
+    parser.add_argument('-f', '--filter', nargs='*', default=None, metavar='cid',
                         help='Zero or more chat IDs to add in a filter whitelist (default is empty, all chats allowed)')
     parser.add_argument('-n', '--nicknames', nargs='*', default=[], metavar='name',
                         help='Any possible nicknames that the bot could answer to.')
@@ -112,7 +112,7 @@ def main():
                          archivist,
                          logger,
                          admin=args.admin_id,
-                         filter_cids=filter_cids,
+                         cid_whitelist=filter_cids,
                          nicknames=args.nicknames,
                          wakeup=args.wakeup,
                          memory=args.capacity,