At the beginning of the play Richard 3rd, Richard, the play's protagonist, then known as the Duke of Gloucester, steps onto the stage and addresses the audience directly.
In his 42 line monologue, he tells of the days of peace that follow his brother's ascension to The Throne of England. How arms that used to serve in battle are now hung as decorations. How war time marches are no longer needed. How days of strife have given way to ease and leisure.
Yet rather than enjoying the fruits of his family's struggles in reaching the seat of power, Richard rejects them.
He doesn't indulge in cheap vanities or easy luxuries. Neither was he fashioned by nature to do so, as so he says. Shakespeare bases his portrayal of Richard on historical accounts that emphasized his deformities. A hunchback. Misshapen. Born with teeth that were able to bite those who cared for him. These are spelled out explicitly in this opening scene:
"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;" — The Life and Death of Richard the Third, Act I, Scene I, Lines 18–23 (Gloucester)
Perhaps at this point, as a first time reader of Shakespeare, it would be easy to feel somewhat sorry for Richard, Duke of Gloucester. He's fully aware that the forces of nature dealt him with a poor hand in life outside of his control. So bad that even the dogs on the street bark as he passes by.
Yet Richard is also a man of ambition. His restless mind focuses not on the pleasures before him, but on a greater prize: the Crown. And in this ambition, he's willing to take a dark path. It is in the following lines, therefore, that we have perhaps one of the most ambiguous words Shakespeare ever put to paper: determined.
"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." — The Life and Death of Richard the Third, Act I, Scene I, Lines 28–31 (Gloucester)
But why is 'determined' so ambiguous? In Shakespeare's time, it had a double meaning. It could mean that someone had resolved themselves to a state of being or a course of action. It also meant being driven by forces beyond a person's control. It's a word loaded with meaning. Rather, both can be true, either one, or perhaps not at all. Maybe it's just a story Richard tells himself to set upon his goals. Perhaps the following words are equally important: 'to prove a villain'. Prove could mean assuming a role, trying to live up to something, or trying to realize his own self-imposed identity.
This ambiguity continues throughout the play, yet is never resolved by Shakespeare. True to word, the crimes of Richard 3rd are played out, and it's left to the audience to decide whether it's destiny, choice, or a story that drives him.
Perhaps the closest we get to understanding the character comes on the eve of the Battle of Bosworth field. Visited by the ghosts of those who he had murdered, Richard awakes to face his own guilty conscience. Shakespeare gives us a glimpse into the hatred, loneliness, and self-doubt the character faces. The identity he had assumed to 'prove a villain' in carrying out the crimes he committed begins to crack.
Shakespeare's Richard 3rd is not black or white. No matter how you try to measure his character, the scales are always tipped on one side or another by the weight of one ambiguous word: determined.