Being ignorant is not so much a shame, as being unwilling to learn.

A learned blockhead is a greater blockhead than an ignorant one.

To inquisitive minds like yours and mine the reflection that the quantity of human knowledge bears no proportion to the quantity of human ignorance must be in one view rather pleasing, viz., that though we are to live forever we may be continually amused and delighted with learning something new.

...It is in the religion of ignorance that tyranny begins...

The only thing that is more expensive than education is ignorance.