This book collects the two most important political writings of Jean-Jacques Rousseau: Discourse on Political Economy and On Social Contract. Rousseau is one of the most original and influential philosophers, having a profound effect on everyone and everything from the French Revolution - and, depending on whom you ask, the American - to Marx to Tolstoy. His range was literally encyclopedic, but he is probably best remembered for political writings. Anyone looking to get a good overview of these will do well to start here, as this basically has all of his strictly political work, but anyone wanting a wider overview must look elsewhere.
Discourse on Political Economy essentially takes the next step of asking how we can legitimize and improve such a corrupt society. It does not have easy answers but does reject the seemingly obvious one that we return to a primitive state; Rousseau has often been charged with this, but he actually explicitly denies it. This Discourse is far less original but has several salient points and is well-written. It is an important contribution to the question that has dominated Western thought since at least Plato and essential reading for anyone with even the slightest interest in it.
On Social Contract is now considered Rousseau's most important work, and it is easy to see why. He of course did not invent the social contract; Thomas Hobbes' 1651 Leviathan is generally considered its foundation, but elements are visible at least as far back as Plato. It had dominated Western political thought since Hobbes, though, and Rousseau's contribution is one of the most important. He looks at the question more thoroughly and systematically than anyone since Hobbes and, though he admired the latter, comes to almost the opposite conclusion. His arguments for a social contract are strong - nay, near-undeniable - but, more importantly and unlike many, he actually goes into how to implement one in considerable detail. The work is again remarkable for being very well-written. As it is significantly longer than the Discourses, the quality is not as uniform; several chapters, especially those on the Roman republic, are more or less tangential, and there are other weak spots. That said, the vast majority is extremely engaging and generally lucid. One can come away from On Social Contract with an almost spiritually intense belief in its central tenets, and many have; Poland and Corsica both asked Rousseau to propose a constitution, and the French Revolution may well not have happened without him. The book was enormously influential throughout the twentieth century and continues to be. Unfortunately, though, the vaguest parts are precisely those that are the most specific about how Rousseau's social contract can be actualized. His infamous claim that we must be "forced to be free" has long been controversial, as have related statements about the General Will's infallibility, absolute sovereignty, anti-monarchialism, and religion. They are near-paradoxical at times and open to a wide interpretation variety. This is how Rousseau has been able to influence people at opposite ends of the political spectrum. He has been credited or blamed - depending on point of view - for everything from the French Revolution to Hitler and Stalin. His philosophical ties to these last have been near-definitively refuted in recent decades, but the book is such we can see how such misconceptions arose. Near-insurmountable pessimism about his own ideals, including his famous statement that only gods would be fit for a democracy, has also frustrated even his strongest admirers. As with all important controversial books, the key is to form one's own conclusions. Few seminal works have greater potential for viable individual interpretation and general applicability.
This gets to the crux of reading Rousseau; he probably invokes the greatest reaction disparity of all philosophers. One almost literally either loves or hates him. Many have idolized and based their whole lives and philosophies on him; at least as many have done the opposite. Those who value originality and writing qualities like general lucidity and conciseness will likely love Rousseau, as he here excels nearly all philosophers and even many literary writers. However, empiricists and others who value truth and facts above all, as well as those who are eminently practical, may well loathe him. Discourse on Inequality's infamous statement that it will ignore facts because they have no bearing on the issue has appalled many ever since publication. Even so, Rousseau's importance and influence are such that anyone seriously interested in philosophy or political thought must read him. Not everyone will agree, but he has been at least as valuable to dissenters as to advocates, however differently.
In sum, those wanting an essential overview of Rousseau's political writings will be interested in this, especially if they want some context and commentary.