[12] Third Edition, p. 54.

[13] Mind, Vol. XI, p. 166 f.

[14] Ibid., p. 166.

[15] Ibid.

[16] Op. cit., p. 170.

[17] Ibid.

[18] Op. cit., p. 172.

[19] Ibid.

[20] Op. cit.