i don't know what causes vanity but i think people who're confident or over confident usually are also very vain
when someone is nice to a vain person, the vain person thinks that person really means it because the vain person is confident of his/her own value so it believes the forked tongues and therefore its susceptible to fall for sycophancy and by that manipulation
of course when a vain person is told about how people are using him, the vain person reacts angrily because the vain person cannot comprehend how could someone falsely praise someone
every vain person needs someone who will protect them from manipulators even if it means hitting the vain person in the head if they don't listen... this is why i need my wife
when someone is nice to a vain person, the vain person thinks that person really means it because the vain person is confident of his/her own value so it believes the forked tongues and therefore its susceptible to fall for sycophancy and by that manipulation
of course when a vain person is told about how people are using him, the vain person reacts angrily because the vain person cannot comprehend how could someone falsely praise someone
every vain person needs someone who will protect them from manipulators even if it means hitting the vain person in the head if they don't listen... this is why i need my wife
