doubt such advance demands many favorable concurrent circumstances; but it may well be doubted whether the most favorable would have sufficed, had not the rate of increase been rapid, and the consequent struggle for existence extremely severe."[21] The end or aim of morality is the general good, rather than the general happiness, though "no doubt the welfare and the happiness of the individual usually coincide; and a contented, happy tribe will flourish better than one that is discontented and unhappy.... As all wish for happiness, the 'greatest happiness principle' will have become a most important secondary guide and object; the social instinct, however, together with sympathy (which leads to our regarding the approbation and disapprobation of others), having served as the primary impulse and guide."[22] And with regard to the future, Darwin says: "Looking to future generations, there is no cause to fear that the social instincts will grow weaker, and we may expect that virtuous habits will grow stronger, becoming perhaps fixed by inheritance. In this case the struggle between our higher and lower impulses will be less severe, and virtue will be triumphant."[23] FOOTNOTES: [1] P. 381. This essay originally formed part of the chapter on "Instinct" in "The Origin of Species," but was omitted for the sake of condensation. [2] Vol. I. p. 319. [3] Pp. 320, 321. [4] Appendix to "Mental Evolution in Animals," pp. 378, 379. The italics are my own. [5] "The Origin of Species," II. p. 286. [6] Ibid. I. pp. 353, 354. [7] "The Origin of Species," I. pp. 321, 322. [8] Ibid. I. pp. 12-17. [9] Appendix to "Mental Evolution in Animals," pp. 370, 383; see also "The Descent of Man," I. p. 102 _et seq._; and "Nature" for Feb. 13, 1873, introduction to a letter to the editor from William Higginson. [10] P. 103. [11] Pp. 160, 161. [12] P. 161. [13] See also p. 171. And, p. 172, sympathy is designated as "a fundamental element of the social instincts." [14] P. 178. [15] Pp. 174, 178. [16] P. 173. [17] "Descent of Man," I. p. 199, etc. [18] Ibid. p. 179. [19] Ibid. pp. 199-209. [20] Ibid. p. 212. [21] Ibid. pp. 219, 220. [22] Ibid. p. 185. [23] Ibid. p. 192. ALFRED RUSSEL WALLACE