Recently we posted a list of resources that refute Jonathan Edwards and Calvinistic compatibilism and defend genuine free will (http://evangelicalarminians.org/refuting-edwards-and-calvinist-compatibilism-and-arguments-against-genuine-free-will/). Some of them are pretty hefty. So if you would like to get to the heart of the debate by reading something relatively brief that refutes the main thrust of compatibilism as it is frequently presented by Calvinists today, then take a look at
Thomas Ralston on Freedom of the Will Part 9: The Doctrine of Motives
It provides a concise, manageable treatment of the heart of Edwards’ view/compatibilism as it is often presented today. Now certainly it would be good to read Ralston’s whole argument on the issue, which is relatively concise too for a treatment of the whole issue (basically about article length, though contained in 9 segments on our site). And it would obviously be ideal to read Whedon, who is much more thorough and detailed. But if you want to get at the heart of the issue quick, Ralston does a great job in his section on the doctrine of motives.