What is the definition of 'fool' in Theravada Buddhist text? The Lakkhana Sutta says,


  Endowed with three things, monks, a fool can be known as a fool. What three? By bodily misconduct, by verbal misconduct, by mental misconduct. Endowed with these three things, monks, a fool can known as a fool.


But everyone has bodily misconduct, verbal misconduct and mental misconduct (I say that because we make mistakes from time to time, at least to a certain extent).

So how to differentiate between a fool's (bodily, verbal and mental) misconduct, compared to a wise person's (bodily, verbal and mental) misconduct?
In SN 12.19 (Bala-pandita Sutta: The Fool &amp; the Wise Person) the Buddha explains &quot;what distinguishing factor is there between the wise person &amp; the fool&quot;:

The Blessed One said, &quot;The ignorance with which the fool is obstructed, the craving with which he is conjoined, through which this body results: that ignorance has not been abandoned by the fool; that craving has not been destroyed. Why is that? The fool has not practiced the holy life for the right ending of stress. Therefore, at the break-up of the body, he is headed for a [new] body. Headed for a body, he is not entirely freed from birth, aging, death, sorrow, lamentation, pain, distress, &amp; despair. I tell you, he is not entirely freed from stress &amp; suffering.
&quot;The ignorance with which the wise person is obstructed, the craving with which he is conjoined, through which this body results: that ignorance has been abandoned by the wise person; that craving has been destroyed. Why is that? The wise person has practiced the holy life for the right ending of stress. Therefore, at the break-up of the body, he is not headed for a [new] body. Not headed for a body, he is entirely freed from birth, aging, death, sorrow, lamentation, pain, distress, &amp; despair. He is, I tell you, entirely freed from stress &amp; suffering.&quot;