*Sarah Dry  did a PhD in the History and Philosophy of Science. Her book The Newton Papers: The Strange and True Odyssey of Isaac Newton's Manuscripts is published this month by Oxford University Press. Read Sarah Dry's blog here.
In November of 1690, Isaac Newton sent a long essay to his friend, the philosopher and radical thinker John Locke. In it, Newton set forth the reasons he thought scripture had been corrupted over the centuries - and for his own disbelief in the Trinity, a key tenet of Anglicanism. He asked Locke to see about translating the work into French and having it published - anonymously - on the Continent. The contents of the essay were so controversial that Newton dared not attach his name to it.
The episode was unique. Never again would Newton come as close to publishing such sensitive material about his dramatically unorthodox religious beliefs. But the episode was also indicative of Isaac Newton's lifelong relationship with publication. Never able merely to reject print culture outright - the rewards of priority, communication and prestige were too great for that - Newton was nevertheless intensely averse to the lack of control that accompanied publication.
Through a long and surprising series of events, Newton's private papers, (including the original draft of the essay he sent to Locke) have survived to the present day. In The Newton Papers: The Strange and True Odyssey of Isaac Newton's Manuscripts, I tell their story for the first time. Throughout the course of the nearly three centuries since Newton's death, the papers have been examined only briefly and intermittently by a handful of people. Through a combination of suppression, neglect, and confusion, the complex, disordered papers were cloaked in mystery until very recently. Now the Newton Project has transcribed nearly 6.5 million words of the writing, including nearly all of his most private religious works. What was once private has become radically public.
The private Newton
What are we to make of the availability of this new material? Since these writings were largely inaccessible until now, how can we relate them to the much more public image of Newton, created in part by his two great publications, the Principia and the Opticks?
These questions have challenged scholars since the papers started to become available in the 1960s. Some have sought to unify the archive, seeking to make connections between the science and the non-science. Others have opted for a Newton of many parts, each free to pursue distinct projects. Such differences of analysis are partly due to changing historical tastes. In this sense, each generation gets the Newton it requires - or deserves. As further research is done on the papers, new arguments will undoubtedly be made about how to understand their contents. The drive to understand the inner world of a man as creative and intellectually important as Newton remains strong.
Newton's attitude towards publication is one thread that can be used to stitch the archive together, should we wish to do so. Newton despised dispute. Once he had convinced himself that his answers to a question - whether of scientific, mathematical, or theological nature - were correct, he was loath to enter into a debate in order to prove it to others. Once his words were published, there was little he could do about how they were interpreted. Consequently, he was often very reluctant to make anything public.
The treatise that Newton sent to Locke was never published during his lifetime. A few months after he sent it, Newton had an abrupt change of heart. 'I design to suppress them,' he explained, begging Locke to stop the translation and printing of his words. He had decided that the contents of the essay were too heretical to risk making public in any form.
Newton was right to be wary. Though Locke returned Newton's own copy of the essay, the translator retained a copy from which several subsequent copies were made. These circulated throughout the 18th century, and Newton's own name was attached to an unauthorised and inaccurate publication of the entire essay in 1754.
Newton's reluctance to publish did not only apply to heretical religious beliefs. He published very little of his mathematics during his lifetime. Had he been quicker to do so, he would have avoided the contentious priority dispute with Gottfried Liebniz over the discovery of the calculus. With his natural philosophy and his optics, Newton was more open, but only when friends and supporters convinced him it was in his interest to be so. If Newton had his own way, he would most likely have communicated his scientific discoveries sparingly, in manuscript rather than print, and only to those he deemed friends.
Would Newton be horrified to know that his most private thoughts are now accessible to anyone online? Probably. But he had himself taken care to save these papers throughout his long life. He believed that the day would come when his version of Christianity would be revealed to the masses as the true religion. Perhaps he hoped that then his papers would be able to be freely read and distributed. Theologically speaking, that day has not come, but what has arrived is the moment when Newton's private beliefs - though still vexing and difficult to understand - are a part of his public image.