 A fourth reaction, that of Forbes, is to propose a mixed solution: he holds that for some individuals (including human beings and trees) suitable candidates for non-trivial individual essences can be found (by appeal to distinctive features of their origins), although for others (including most artefacts) it may be that no suitable candidates are available, in which case counterpart theory should be adopted for these cases (see Forbes 1985, Chs 6–7).