a little mole once said to his mother:

"why, mother, you said i was blind! but i am sure i can see!"

mother mole saw she would have to get such conceit out of his head. so she put a bit of frankincense before him and asked him to tell what it was.

the little mole peered at it.

"why, that's a pebble!"

"well, my son, that proves you've lost your sense of smell as well as being blind."

boast of one thing and you will be found lacking in that and a few other things as well.