Perry Miller qualifies his seeming dismissal of Edwards’ ability as a logician: “…Freedom of the Will is the cornerstone of Edwards’ fame; it is his most sustained intellectual achievement, the most powerful piece of sheer forensic argumentation in American literature. [The book] “is considered by logicians one of the few proofs in which the conclusion follows inescapably and infallibly from the premises.” Edwards is America’s preeminent philosopher. However, Miller adds, “it is the least valuable of his major productions…for American literature.”
What set Edwards apart from his eighteenth-century contemporaries was his profound reading and insight into Locke’s sensational psychology and Newton’s physics. Out of his readings and insights, Edwards developed a theory of language and a powerful linguistic technique that triggered the religious revival historians call the Great Awakening. For Edwards, “there could be no warfare between religion and science, or between ethics and nature.” For Jonathan Edwards
“went directly to the issues of his age, defined them, and asserted the historic Protestant doctrine in full cognizance of the latest discourses in both psychology and natural science. That the psychology he accepted was an oversimplified sensationalism, and that his science was unaware of evolution and relativity, should not obscure the fact that in both quarters he dealt with the primary intellectual achievements of modernism, with the assumptions upon which our psychology and physics still prosper: that man is conditioned and that the universe is uniform law. …Locke is, after all, the father of modern psychology, and Newton is the fountainhead of our physics; their American student, aided by remoteness, by technological innocence, and undoubtedly by his arrogance, asked in all cogency why, if the human organism is a protoplasm molded by environment, and if its environment is a system of unalterable operations, need mankind any longer agonize, as they had for seventeen hundred years, over the burden of sin? By defining the meaning of terms derived from Locke and Newton in the light of this question, Edwards established certain readings so profound that only from the perspective of today can they be fully appreciated.”
If one queries what that “historic Protestant doctrine” is, we may turn to Miller’s succinct estimate as definitive: “Edwards brought mankind, as Protestantism must always bring them, without mitigation, protection, or indulgence, face to face with a cosmos fundamentally inhuman.”
“Many definitions of Puritanism have been offered by historians. For the student of American culture, I suspect that the most useful would be simply that Puritanism is what Edwards is.”
The interest of Edwards’ interpretation, on the other hand, is that he, while taking stock of everything in Hutcheson, and affirming no less that whatever is, is right, also could further discover in the workings of a perfect universe a principle of absolute, ineradicable evil. It was, he could say as early as the “Notes,” self-love, or what today would more readily be called egotism. It is evil not because it mars in the slightest the perfection of the best of all possible worlds, but evil in the inward sense, where it is a want of beauty. It is, in fact, not love at all, it is “merely an inclination to pleasure, and averseness to pain.” It is life as lived solely for the objective good, on only the one level instead of on both levels, without the perception of both the objective and the inherent. Devils and damned creatures love themselves, not for any good they see in themselves, but because they have an aversion to the disagreeable…Self-love, in short, is evil, yet it is no affection…As Edwards declared in the Religious Affections, take away this insight, and God Himself, with all the created universe, is an infinite evil. Which is to say that the will of man must do what nature calls for;  there can be no evil in the scientific order, but evil exists, and its hiding place is the will of man.