Boyle, Robert (1627–91), natural philosopher, was born 25 January 1627 at Lismore Castle, fourteenth child and seventh son of Richard Boyle (qv), 1st earl of Cork, and his second wife, Catherine Fenton (qv). Robert was brought up in Ireland till sent to Eton College, aged eight, in 1635. His father withdrew him from Eton in 1638 and, after a year in which he was educated privately at his father's English seat, Stalbridge House in Dorset, he set out on a continental tour under the tutelage of the huguenot savant Isaac Marcombes; he visited France and Italy and continued his education during a stay in Geneva from 1642 to 1644.
Returning to England, he initially settled on the estate at Stalbridge, which by this time had been bequeathed to him, and it was here that his career as a writer began. Initially, he devoted himself not to natural philosophy but to compositions written in a self-consciously literary style in which he advocated the pursuit of moral rectitude. Some of Boyle's writings from this period were published by him in modified form later in his life, while others were first published in the late twentieth century.
In 1649 Boyle's preoccupations changed dramatically when he erected a laboratory at Stalbridge and began to experiment for the first time. His writings from the years that follow display an acute sense of the value of such experimental knowledge in the defence of religion, which was to remain with him for the rest of his life: this is perhaps seen most clearly in his ‘Of the study of the book of nature’ (c.1650), which has recently been published for the first time in vol. xiii of the new edition of his Works.
In the early 1650s Boyle came into contact with the American chemist George Starkey, alias Eirenaeus Philalethes, and it is clear that this liaison had a profound effect on Boyle. Through Starkey, Boyle was introduced to the work of J. B. van Helmont – whose influence on Boyle is now known to have been far greater than was once thought – and to more sophisticated chemical experimentation than he had practiced previously. Boyle pursued similar interests in conjunction with contacts made through the ‘intelligencer’ Samuel Hartlib, with whom he carried out an extensive correspondence at this time. From this period onwards, Boyle retained a deep interest in alchemy, as recent study has made clear.
Between June 1652 and July 1654 Boyle spent all but about three months in Ireland. Towards the end of his stay, he fell seriously ill of a dropsy which permanently affected his eyesight. Although his profuse income remained substantially based on his Irish landholdings, he never visited Ireland again.
A new phase in Boyle's career opened with his move to Oxford in 1655 or 1656 to join the group of natural philosophers assembled there under the auspices of John Wilkins, warden of Wadham College, including such luminaries as Seth Ward, Thomas Willis, and Christopher Wren. Boyle now came into contact with a wider range of natural philosophical ideas, including the mechanical philosophy as adumbrated by Descartes and others, which profoundly affected his subsequent intellectual life. It was also now that Boyle discovered an extraordinary facility as an author, producing a torrent of writings which began to make their way into print over the following decade, establishing him as the international celebrity that he remained for the rest of his life.
The first work of natural philosophy that Boyle published was in many ways the most important, his New experiments physico-mechanical, touching the spring of the air and its effects (1660). This derived from his interest in the pneumatic experiments of Otto von Guericke, about which he heard in the late 1650s. With the help of Robert Hooke, his assistant and later a significant natural philosopher in his own right, Boyle devised a vacuum chamber which could be used to assess the characteristics and functions of air, notably by studying the effect of its withdrawal on flame, light, and living creatures. In his book he presented a series of experiments of extraordinary ingenuity, together with reflections on them, in a format that was to prove as influential as it was novel.
Hardly less significant was a book published by Boyle in 1661, Certain physiological essays. In part, this was important for the sophisticated rationale that it offered for the practice of experiments and their presentation in the form of ‘essays’. The work exemplified this particularly in the ‘Essay on nitre’, written early in Boyle's Oxford period, in which he showed how the changes that could be brought about on saltpetre by chemical means could be explained in ‘corpuscular’ terms (the name he coined for his version of the mechanical philosophy). A number of Boyle's later writings were presented as sequels to this epoch-making essay.
Also significant was a further programmatic work written in the late 1650s, the first ‘tome’ of Boyle's Usefulness of natural philosophy (1663), which comprised a series of essays justifying the study of natural philosophy partly on religious grounds and partly on practical ones. The section of this work published in 1663 dealt disproportionately with the medical applications of natural philosophy, but Boyle's essays on more miscellaneous aspects of the utilitarian benefits of science came out in a sequel published in 1671.
The books that Boyle produced in the early to mid 1660s also included his famous, if rather diffuse, The sceptical chymist (1661), in which he criticised the principles of ‘vulgar’ chemists. In addition, he responded to critics of Spring of the air, thus enabling him to expound and vindicate his ideas more fully: he was to publish further work on pneumatics in the 1670s. The mid 1660s saw the publication of Boyle's massive experimental ‘histories’ of Colours (1664) and Cold (1665), which further exemplified his programme of using experimental and observational data to vindicate corpuscular explanations of nature. Equally important was his Origin of forms and qualities (1666), in which he attacked Aristotelian notions, arguing for the superior intelligibility of mechanical explanations.
The Royal Society had been founded in 1660, and Boyle was central to the society in its early years. His publications were widely seen as exemplifying its aims and objectives and they were heavily promoted in the journal Philosophical Transactions, inaugurated by the society's first secretary, Henry Oldenburg, himself a protégé of Boyle.
From the later 1660s a further phase in Boyle's career opened; it may not be coincidental that this was juxtaposed with his move in 1668 from Oxford to London, where he was to live in the house of his sister, Katherine Jones (qv), Lady Ranelagh, for the rest of his life. At this point Boyle ceased to publish substantial, continuous treatises, instead issuing a series of rather disparate volumes of ‘tracts’, often more essayistic in form and sometimes more speculative in nature, dealing with such themes as the ‘cosmical qualities’ or ‘effluviums’ of things, though this was not exclusive of the publication of case studies of the mechanical philosophy, as seen in his Experiments, notes &c. about the mechanical origin of qualities (1675). Boyle's unabated experimental acumen is revealed by his trials in the late 1670s of the qualities of phosphorescent substances which came to the attention of English virtuosi at that time.
Though Boyle had earlier brought out devotional works alongside his scientific output, notably his Seraphic love (1659) and Occasional reflections (1665), the 1670s saw him publishing works concerned more overtly than hitherto with the mutual relations of science and religion. In such works as The excellency of theology, compared with natural philosophy (1674) and Some considerations about the reconcileableness of reason and religion (1675), Boyle dealt with issues to do with the religious significance of natural philosophy and with the role and limitations of reason, topics to which he was to revert repeatedly in publications of his later years.
Another topic on which he was to publish profusely in his later years concerned the medical spin-offs from natural philosophy, taking up one of the themes of The usefulness of natural philosophy, though he thought better of a direct assault on the medical profession. Among his works in this field was his Medicina hydrostatica (1690), which explored the value of the study of specific gravity in a medical context, while a volume published in 1685 comprised analytical tests of mineral waters.
Boyle also remained active throughout his life as a philanthropist and a promoter of missionary and other concerns. He was governor of the Corporation for the Propagation of the Gospel in New England, or New England Company, from 1662 to 1689, and he promoted various books aimed at the mission field, not least in the Near East, from 1660 to 1677. It is in this context that one should see his patronage in the early 1680s of the reprinting of the Irish translation of the New Testament and the publication of the William Bedell (qv) translation of the Old Testament. Subsequently, these translations were also distributed in the Scottish Highlands.
Boyle suffered a severe stroke in 1670, and he was increasingly infirm in his later years. He drew up an elaborate will in the summer of 1691, evidently feeling that the end was near, and he died 30 December 1691 within eight days of his beloved sister, Katherine, whose house he had shared since 1668. A memorable funeral sermon was preached by his confidant, Gilbert Burnet, bishop of Salisbury, at St Martin-in-the-Fields, on 7 January 1692.
The Boyle letters and papers are housed at the Royal Society in London, where they were deposited in 1769. For a catalogue of the archive, see Michael Hunter at al, The Boyle papers: understanding the manuscripts of Robert Boyle (2007). The Royal Society also has portraits of Boyle by Johann Kerseboom and John Riley. Various other versions of the Kerseboom portrait exist. The three other principal images of him are (1) a sculpture of him as a boy on the tomb of the 1st earl of Cork in St Patrick's cathedral, Dublin; (2) an engraved portrait based on a drawing by William Faithorne now in the Ashmolean Museum, Oxford; and (3) a medal struck by C. R. Berch from a lost ivory medallion executed by Jean Cavalier. For a full account, see R. E. W. Maddison, ‘The portraiture of the Honourable Robert Boyle’, Annals of Science, xv (1959), 141–214. The standard editions of his writings are Michael Hunter and Edward B. Davis (ed.), The works of Robert Boyle (14 vols, 1999–2000), superseding the earlier edition by Thomas Birch (1744, reprinted 1772, 1965); Michael Hunter, Antonio Clericuzio, and Lawrence M. Principe (ed.), The correspondence of Robert Boyle (6 vols, 2001); 'The work-diaries of Robert Boyle' (revised 2004, available online at www.livesandletters.ac.uk/wd/index.html); J.J. McIntosh (ed), Boyle on atheism (2005); and John T. Harwood (ed.), The early essays and ethics of Robert Boyle (1991). Michael Hunter (ed.), Robert Boyle by himself and his friends (1994) is a collection of key early biographical sources.
Boyle left an important legacy. He was the leading exemplar of the new, experimental philosophy in late seventeenth-century England, his profuse books proving influential in exemplifying how experimental enquiries should be executed and reported, and in emphasising the significance of the ‘matters of fact’ obtained by such means. This was combined with a wariness of premature systematisation which was also highly influential – though Boyle's work was far from aimless, and his investigations were underlain by clear, if eclectic, explanatory goals.
Boyle was also a paradigm in terms of the broad affiliations of scientific inquiry. His aristocratic background gave him a patrician demeanour to which his contemporaries almost automatically deferred, and the pursuits to which he devoted himself undoubtedly gained kudos from this. Even more important was Boyle's role as ‘the Christian virtuoso’, to quote the title of one of his last books to be published in his lifetime. Quite apart from the extent to which he exemplified Christian principles in his own life, it now seems that Boyle's intense religiosity helps to explain his experimental activity, in that his laboratory practice can in many ways be seen as an extension of his indefatigable examination of his conscience. Equally significant was Boyle's conviction of the integrity of the study of nature to a proper understanding of religion, something which he not only exemplified in his own work but also promoted posthumously through the series of apologetic ‘Boyle Lectures’ that were inaugurated under one of the provisions of his will. The early enlightenment synthesis of science and religion owed more to Boyle than to anyone else, and the same may arguably also be said for the experimental method of modern science.