sn.46.44 Saṁyutta Nikāya (Linked Discourses)

Witless

Then a mendicant went up to the Buddha … and asked him,
“Sir, they speak of ‘a witless idiot’.
How is a witless idiot defined?”
“Mendicant, they’re called a witless idiot because they haven’t developed and cultivated the seven awakening factors.
What seven?
The awakening factors of mindfulness, investigation of principles, energy, rapture, tranquility, immersion, and equanimity.
They’re called a witless idiot because they haven’t developed and cultivated these seven awakening factors.”