Liberty has restraints but no frontiers. David Lloyd George
The frontiers of knowledge in the various fields of our subject are expanding at such a rate that, work as hard as one can, one finds oneself further and further away from an understanding of the whole. James Meade
In this world, shipmates, sin that pays its way can travel freely, and without passport; whereas Virtue, if a pauper, is stopped at all frontiers. Herman Melville
There are no national frontiers to learning. Japanese Proverb
The lawyer will extend the frontiers of a fight. Japanese Proverb
The war horses are born on the frontiers. Chinese Proverb