Tom Canty and Edward Tudor of The Prince and the Pauper are physically identical but in other ways they are exact opposites. Of course their lives and circumstances are completely opposite, the one is a street urchin and thief, the other a crown prince being reared to be king in a palace. The differences go deeper, however, and their personal traits, the traits that determine their place in the world, are opposites.
Tom is mistreated, disrespected and unloved. Edward is treated magnificently, his every wish matters, and deeply respected and much beloved, even by Henry VIII.
Tom has no personal voice: he can't say who he is. Edward has a strong personal voice and continually says who is is regardless of the persecution that it brings his way. This trait pertaining to voice corresponds to inner personal integrity: Tom lacks it, Edward has it. Because of these factors, Tom can't assert his thoughts while Edward can assert his thoughts and intentions; e.g., while Miles is in the stocks, he asserts that Miles shall be an Earl.
This shows that Tom does not have a strong mind of his own, whereas Edward does have a strong mind of his own. Tom has never learned respect for objects, while Edward values and respects objects rightly. The boys, though antithetically different, have one trait in common. They are both able to see the reality in new situations and to grow and develop in them. Tom has the ability to rise to a nobler state of mind and life. Edward has the ability to learn compassion for outrages he has never seen before.