Queen Margaret. And where's that valiant crook-back prodigy,
Dicky your boy, that with his grumbling voice
Was wont to cheer his dad in mutinies?
(Henry VI part 3, 1.4.514-516)
An integral part of Richard III's identity is his physical deformity. A hunchback, he is not only mocked about his physical appearance by people who barely know him (like Queen Margaret quoted above, who focuses on Richard's disability when talking to his father the Duke of York), but he himself is acutely, painfully self-aware of his appearance and physical challenges:
[Love] did corrupt frail nature with some bribe,
To shrink mine arm up like a wither'd shrub;
To make an envious mountain on my back,
Where sits deformity to mock my body;
To shape my legs of an unequal size;
To disproportion me in every part,
Like to a chaos, or an unlick'd bear-whelp
That carries no impression like the dam.
(Henry VI part 3, 3.2.1644-1651)
Looking at Richard's disability and how it shapes his character, as well as the audience's perception of him, could be an almost never-ending study. However, just one aspect of the deformity that I want to look at is the perception articulated by Queen Margaret in the quotation above - that the disability marks him as a "prodigy," meaning that his exterior appearance serves a sort of sign or portent for the state of his character. Richard's crooked outside, as it is read by his enemies, indicates a crooked soul!
Of course, Richard embraces wickedness and, fulfilling the beliefs of those who hold that the outside matches the inside, does mangle his soul and distort his concience. Could it be that Richard was really born with a worse character than anyone else? His mother does mention that he was always bad:
Tetchy and wayward was thy infancy;
Thy school-days frightful, desperate, wild, and furious,
Thy prime of manhood daring, bold, and venturous,
Thy age confirm'd, proud, subdued, bloody, treacherous...
(Richard III, 4.4.2967-2970)
However, I think it's supported by the text to read Richard's disability not as shaping him in some sort of mystical way, but rather as affecting him by setting him apart from others. Richard is constantly faced with comments and unkind words about his appearance, and based on this he allows his deformity to isolate him; he cuts himself off from certain activities and feels bitterness over the fact that he is left out.
A perfect example is his attitude towards love and women (Richard's relationship with women is a HUGE topic, which deserves a post all its own!). However, for the quick version, it's clear that he feels that his appearance is such that no woman would really want to be with him. Sad, right? This is one of the many times that we can empathize with Richard and hope that he could somehow learn to see himself in a more healthy way. BUT NO - Richard takes his unfortunate situation and makes it WORSE by taking his status as an outsider and expanding it into hatred for anyone who has anything and everything that he feels himself cut off from:
I, that am curtail'd of this fair proportion,
Cheated of feature by dissembling nature,
Deformed, unfinish'd, sent before my time
Into this breathing world, scarce half made up,
And that so lamely and unfashionable
That dogs bark at me as I halt by them;
Why, I, in this weak piping time of peace,
Have no delight to pass away the time,
Unless to spy my shadow in the sun
And descant on mine own deformity:
And therefore, since I cannot prove a lover,
To entertain these fair well-spoken days,
I am determined to prove a villain
And hate the idle pleasures of these days.
(1.1.19-32, emphasis added)