Patanjali has made wonderful analysis of Mind & its unknown contours. Various modifications are:

‘Modification of “False cognition”’:
If I see the table as Chair or mistake person X for person Y, etc, then it is known as False Cognition. One serious situation is that one considers ‘friend’ as ‘enemy’. In one’s lifetime one experiences many such moments.

Once there was a barber, who was poor although he served the king. He could not provide all facilities to his family, but led a contented life. On day while passing thru the jungle, to his surprise he found seven jars containing gold coins, but nobody to claim them. He brought them home and opened one by one. He started feeling he is a Millionaire. When he opened the seventh jar, to his disappointment, the seventh jar was half full.

He started working day and night, with singular purpose of filling the seventh jar, for becoming the richest man. He could not even get proper sleep, eat food, etc. His body became old, yet his mind harped only on filling the seventh jar to become the richest man. Now the barber was on his death-bed and the seven jars were next to his bed. The seventh jar mocked at him, “I have killed so many people like you. My nature is to be empty. Many tried to fill me but failed.”

What is true of the seventh jar is true of the mind also. The mind, is also always half happy and half unhappy. Half contented and half pining & craving for what is not. Where it ought to find pleasure, it ends up finding pain, only pain. What a pity.

This is the example of wrong/false Cognition, and this the source of all human suffering. Hence unless the mind is made contented, the life can never be peaceful & happy.