¹ [Stewart, Balfour and Tait, Peter Guthrie], The Unseen Universe: or Physical Speculations on a Future Stale (2nd edn., London, 1875), pp. xi–xii.Google Scholar The book was first published anonymously, though Stewart and Tait acknowledged authorship in the following year. They later published Paradoxical Philosophy. A Sequel to the Unseen Universe (London, 1878).Google Scholar

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⁹ ibid., 144. For discussion of Whewell see Cannon, W. F., ‘The problem of miracles in the 1830s’, Victorian Studies, iv (1960), 5–32.Google Scholar

¹⁰ See Young, R. M., ‘Darwin's metaphor: does Nature select?’, The Monist, Iv (1971), 442–503.CrossRefGoogle Scholar

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¹³ [Stewart and Tait], The Unseen Universe, p. 192.Google Scholar

¹⁴ ibid., p. 172.

¹⁵ For a full discussion of the role of active principles in Newton's philosophy of nature see McGuire, J. E., ‘Force, active principles and Newton’s invisible realm’, Ambix, xv (1968), 154–208.CrossRefGoogle Scholar

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¹⁹ ibid., p. 64.

²⁰ Young, Thomas, A Course of Lectures on Natural Philosophy and the Mechanical Arts (2 vols., London, 1807), i. 610.Google Scholar

²¹ See McGuire, J. E., ‘Atoms and the “analogy of Nature”: Newton's third rule of philosophizing’, Studies in History and Philosophy of Science, i (1970), 3–58.CrossRefGoogle Scholar

²² [Stewart, and Tait, ], The Unseen Universe, pp. 158f.Google Scholar

²³ ibid., p. 164.

²⁴ ibid., p. 172.

²⁵ ibid., p. 60.

²⁶ ibid., p. 189.

²⁷ ibid., pp. 60ff.

²⁸ Reid, Thomas, Essays on the Active Powers of the Human Mind [1788], ed. Brody, B. (Cambridge, Mass., 1969), p. 47.Google Scholar

²⁹ Bain, Alexander, Logic (2 vols., London, 1870), ii. 30fGoogle Scholar; also Logic (2nd edn., 2 vols., London, 1896), ii. 20f.Google Scholar Tait attacked Bain's use of the term ‘force’ in the first edition of the Logic in an address to the University of Edinburgh (Nature, iii [1870], 89f.)Google Scholar, scathingly pointing out that Bain's ‘force’ should be replaced by ‘energy’. Bain's use of ‘force’ here is in line with the tradition discussed by Professor J. E. McGuire and myself in the paper cited in note 16. Tait took a relational view of force but a substantive view of energy.

³⁰ The performance did not satisfy William Kingdon Clifford, who savaged the book in the Fortnightly Review, concluding that ‘It is clear that the good old gods of our race—sun, sky, thunder and beauty—are to be replaced by philosophic abstractions—substance, energy, and life, under the patronage respectively of the persons of the Christian Trinity’; see Clifford, , Lectures and Essays (2 vols., London, 1879), i. 251.Google Scholar