¹ Cambridge University Library, Add. 3996, ff. 88–135. Newton's exact title, on f. 88, is Questiones quaedam Philosophicae. The irony that might be read into the title by accepting Questiones instead of Quaestiones is a form of wit in which Newton never indulged, and the whole tenor of the passage clearly indicates that Quaestiones was intended.

A. R. Hall was the first to draw attention to Newton's student notebooks, and specifically to the Quaestiones quaedam Philosophicae, in ‘Sir Isaac Newton's Note-book, 1661–65’, Cambridge Historical Journal, 1948, ix, 239–50.Google Scholar This article, together with another by Hall, , ‘Further Optical Experiments of Isaac Newton’, Annals of Science, 1955, xi, 27–43CrossRefGoogle Scholar, and parts of the volume he recently published with his wife, Unpublished Scientific Papers of Isaac Newton, Cambridge, 1962Google Scholar, constitutes the major exception to the ‘virtual blank’ mentioned above in our knowledge of Newton's early work.

² Richard Holdsworth, Directions for a Student in the Universitie, Emmanuel College MS. I.2.27. Newton did use the empty spaces in a large commonplace book started by ‘B. Smith’ (Newton's step-father?) in 1612; Newton used it for mathematics and mechanics and called it his ‘Waste Book’. (Cambridge University Library, Add. 4004.)

³ Magirus, Johannes, Physiologiae Peripateticae Libri Sex cum Commentariis, Cantabrigiae, 1642.Google ScholarFr. Eustachii A. S. Paulo, ex Congregatione Fuliensi, Ordinis Cisterciensis Ethica, sive Summa Moralis Disciplinae, in Tres Partes Divisa, Cantabrigiae, 1654.Google ScholarStahl, Daniel, Axiomata Philosophica sub Titulis XX. Comprehensa, London, 1652.Google ScholarVossius, Gerardus Joannes, Rhetorices Contractal sive, Partitionum Oratoriarum Libri V, Oxionae, 1631.Google Scholar All of these works went through other editions.

⁴ The earliest entries in the Quaestiones (which are not all concentrated in the first pages) are written in a transitional hand which had discarded several letter forms found in his adolescent hand (e.g., e, c, and r—all of which occasionally reappear in their adolescent form), but had not yet acquired the tiny perpendicular characteristic that distinguished his writing by the end of 1664. I have not found any means by which to assign a definite date to the transitional hand. My estimate, early 1664, rests on a number of factors, the most important of which is the obvious continuity within the Quaestiones, later entries of which can be dated definitely. On f. 93v Newton, using the transitional hand, referred a question on the solar system to a specific page of Descartes' Principia Philosophiae. Unfortunately the exact passage to which I would trace the question does not occur on that page in any edition of Descartes. However, it can more reasonably be matched up with the Weyerstaeten Opera of 1664 than with any other edition. This further confirms the date 1664. On the same page an entry definitely made later records an observation of a comet on 10 December 1664.

⁵ Newton had not necessarily read all of these when he made his first entries. The first Quaestio (‘Off y^e first mater’, f. 88) is based directly on, and often repeats the words of Chapter III, Section II of Charleton, Walter, Physiologia Epicuro-Gassendo-Charletoniana (London, 1654).Google Scholar I argue below that Gassendist atomism was the major influence on the Quaestiones. I am unable to say how much of the influence came via Charleton, and I have not found any notes in the Quaestiones that repeat Gassendi's words verbatim as the first Quaestio repeats Charleton. The titles of Quaestiones 10–14Google Scholar (ff. 94–6), on tactile qualities, do repeat, and in the same order, the tactile qualities Gassendi discusses in Philosophiae Epicuri Syntagma. The important essay ‘Of violent Motion’ (ff. 98–8V, 113–14) repeats Gassendi's conception of motion and appears to be based in part on his Epistolae Tres. De Motu Impresso a Motore Translato. In the same Epistolae there is a phrase very similar to Newton's ‘Amicus Plato …’. When Newton wrote De Gravitatione et Aequipondio Fluidorum, which the Halls date between 1664 and 1668, he drew the discussion of absolute space and time directly from Gassendi's Syntagma Philosophicum. All of these works were available in the Opera Omnia of 1658.Google Scholar Descartes is referred to throughout the Quaestiones; as I say in fn. 4, Newton probably read one of the 1664 editions of the Opera, which included all of the major works. Newton cites Galileo's Dialogues (from the Salusbury translation, London, 1661) on f. 121v; he also cites it on f. 26v of the notebook, although this place is not part of the Quaestiones. Although I have not found a direct citation of the Discourses, the problem of calculating ‘absolute weights’ (f. 121) appears to stem from them. Trinity College has one of the few copies of Salusbury's translation, London, 1665, that were not destroyed by the fire of London. He cites or quotes from Boyle's Spring of the Air, London, 1660, on ff. 90v, 96v, 99, and 111, his History of Cold, London, 1665, on ff. 96v, 100v, and his History of Colours, London, 1664, on ff. 124–4V, 133–5. In another notebook which is somewhat later in date (Add. 3975) Newton took down extensive notes from all of Boyle's books as they appeared during the 1660's. On f. 130 he cites Hobbes, Concerning Body (London, 1655, in its original Latin). He took notes from Glanvill's Vanity of Dogmatizing, London, 1661, on ff. 107V, 109v, and 117; from Digby's Two Treatises, Paris, 1644, on f. 107; from More's Immortality of the Soul (included in A Collection of Several Philosophical Writings of Dr. Henry More, London, 1662) on ff. 89, 104, 105, 117, and 132.Google Scholar

⁶ Newton, , Quaestiones quaedam Philosophicae, ff. 88–9v, 119–20.Google Scholar

⁷ Idem, f. 103v.

⁸ Idem, f. 93.

⁹ Idem, ff. 122–2v.

¹⁰ In the Syntagma Philosophicum, it is true, Gassendi explicitly argued that colours arise from the mixture of light and shadow (Opera, Lyons, 1658, vol. i, p. 434).Google Scholar I take Newton's third alternative to be a reference to the atomic theory of simulacra. Gassendi discussed the theory at length in a chapter on intentional species, although he apparently rejected it in the end (Ibid., vol. i, pp. 441–9).

¹¹ Newton, op. cit., ff. 105v.

¹² f. 101v.

¹³ In The Spring of the Air (The Works of the Honourable Robert Boyle, ed. Birch, Thomas, 5 vols. London, 1744, vol. i, p. 27).Google Scholar

¹⁴ Newton, , op. cit., ff. 111, 112.Google Scholar

¹⁵ In the Quaestiones Newton's comments on heat and cold are mostly notes from Boyle, who equated heat with motion. In a later notebook (Add. 3975, p. 51) Newton implied a similar conception. And his proposal quoted below, to compare the weights of a body when hot and when cold, appears to me to be proposed in a hostile manner—that is, hostile to Gassendi's theory. His fully elaborated conception of heat is found in the Queries.

¹⁶ His discussion of cohesion (f. 90v), for example, assumes the centrifugal force of a vortex. See also the passage on tides quoted above.

¹⁷ Newton, op. cit., f. 121v.

¹⁸ Idem, f. 102.

¹⁹ I call this a Gassendist frame of reference to distinguish the conception of gravity as a phenomenon caused by subtle matter moving toward the earth and bearing bodies down with it from the Cartesian conception in which gravity is considered to be a deficiency of centrifugal impulse. In Gassendi's theory gravity is caused by subtle threads attached to the earth, and Newton's idea here resembles Digby's theory more than Gassendi's.

²⁰ Newton, op. cit., f. 121v.

²¹ Idem, f. 102.

²² Idem, ff. 93–3v.

²³ Idem, f. 96v.

²⁴ Idem, f. 99.

²⁵ Idem, f. 100.

²⁶ Idem, ff. 100v, 111.

²⁷ Idem, f. 103.

²⁸ Idem, f. 90v.

²⁹ Newton MSS., Add. 3970.3, ff. 234, 296.

³⁰ Idem, Add. 3970.3, f. 234.

³¹ Newton, , op. cit., ff. 97, 96v, 94v, 121, 107v, 94.Google Scholar

³² Newton MSS., Add. 3970.3, f. 480v.