Question

the mind is not a vessel to be filled but a fire to be kindled

Answer 1

" The mind is not a mere vessel to be filled, but a fire to be kindled"

Our mind isn't a mere receiver of  thoughts , which gathers them all without any practical usage or without any calculation of its own,  but rather works on a complex process, it finds a meaning for each and every information or thought it comes across, evaluates it and reaches a conclusion.

And when it comes to the fact of mind not being a vessel to be filled, but a fire to be kindled, undoubtedly it's cent per cent true.
The statement itself has numerous meaning however all point to the fire, the ardent thirst , the quest for the ultimate goal of life - "Knowledge".

Our mind isn't to be crammed with knowledge- with facts and other's veiw points  but we have to find knowledge on our own. 

In words of a philosopher - 'True knowledge isn't gained  but made."
Our mind is not a vessel that we let ourselves copy someone knowledgable  to get some of their ideas, their thinking and views . We need to realize that we ought to ignite our own mentality, our own intellect. 

The mind isn't a bottle to be filled with ideas gathered from the exterior world, but a piece of wood that has potentials of its own. It only needs a bit of kindling to set it in the right direction, to set it in the path towards  truth and knowledge.

Many great thinkers of the by gone era have had similar quotes. Socrates , William Butler Yeats and Plutarch included among them.

When we ponder a bit more the saying, its amazing how very deep a meaning it offers. 
Consider this single instance- suppose Da Vinci copied someone else's art and didn't let the windows of his imagination fly open . We would have one of the greatest loses ever. I don't need to tell you any further.

So my friends as bearers of young blood and the future citizens of this planet , instead of cramming our heads with other's ideas , lets set our mind on fires, lets be original each one of us setting on quests of wisdom.