How we cite our quotes: (Act.Scene.Line). Line numbers correspond to the Norton edition.
Quote #1
"I am determined to prove a villain"(1.1.1).
In this line from the play's opening speech, Richard reveals to us his plans to take the crown by force. There are a couple different ways to interpret this line, depending on how we define the word "determined."
If we take "determined" to mean "resolved," then Richard is implying that he's made a personal decision to be a villain and is willing to do whatever it takes to get the crown. This is typical Richard, always going out of his way to tell us how smooth he is and that he's the one who makes everything happen. (This works in favor of the "free will" argument.) But, read a different way, the word "determined" can also mean "pre-determined" or "fated," which suggests that Richard is not acting of his own free will, but rather God's.
Quote #2
If heaven have any grievous plague in store
Exceeding those that I can wish upon thee,
O, let them keep it till thy sins be ripe, (1.3.11)
Margaret is always cursing Richard and calling on divine justice to punish crimes he committed in the past. In this way, Margaret suggests that history is shaped by providential design.
Quote #3
I do the wrong, and first begin to brawl.
The secret mischiefs that I set abroach
I lay unto the grievous charge of others.
Clarence, whom I, indeed, have laid in darkness,
I do beweep to many simple gulls
Namely, to Hastings, Derby, Buckingham;
And say it is the queen and her allies
That stir the king against the duke my brother.
Now, they believe it; and withal whet me
To be revenged on Rivers, Vaughan, Grey:
But then I sigh; and, with a piece of scripture,
Tell them that God bids us do good for evil:
And thus I clothe my naked villany
With old odd ends stolen out of holy writ;
And seem a saint, when most I play the devil. (1.3.28)
Richard is always bragging about how he's so crafty and smooth when he lies, cheats, and murders his way to the crown. Here he gloats about committing terrible crimes while blaming them on others. He's also fond of quoting passages from the Bible in order to hide his "naked villainy" from everyone. In other words, Richard behaves like a saint to disguise his bad behavior.
According to literary critic Stephen Greenblatt, this is classic "Machiavellian" behavior. Niccolò Machiavelli's The Prince (1532), was a "how-to" guide for rulers about holding on to power. Machiavelli argued that being a successful leader had nothing to do with being a nice person or doing the right thing. Instead, it's about being inventive, manipulative, charismatic, crafty, and willful.
Why does this matter? Well, when Shakespeare portrays Richard as a "machiavel," he's suggesting that Richard behaves according to his own free will.