mindless
adj
-
Having no sensible meaning or purpose.
-
Heedless.
-
Overly repetitive and unchallenging.
-
Lacking a mind.
-
Showing a lack of forethought or sense.
two sandwiches short of a picnic
How often have the words mindless and two sandwiches short of a picnic occurred in a corpus of books? (source: Google Ngram Viewer )