  The relation of the form-copy to the particular is a real problem. The crucial issue is whether form-copies are dependent on particulars, especially whether their claim to be individual or unit-properties is only as good as the company they keep. Part of the difficulty results from the metaphor Plato's uses throughout the last stage of the Final Argument in the Phaedo. In anticipation of what will be his ultimate ‘proof’ of the immortality of the soul, Plato contends that when something possessed of an essential property, as for instance snow possesses cold, is confronted by the ‘opposite’, heat, then the-cold-in-the snow must withdraw or perish. (The soul, because it cannot perish, must therefore withdraw.) Which of the two possibilities developed in the military metaphor does Plato envisage for form-copies: do they ‘withdraw or perish’? It is a struggle to understand just what the military metaphors amount to, but if the form-copies perish at the approach of their opposite, this suggests that form-copies are dependent on the particulars to which they  belong.[19]  Those who deny that form-copies are bona fide beings cite their perishing as a principal reason to take them as nothing more than a metaphor for the particular's (temporary) participation in the Form. Conversely, if they are able to withdraw, they are in some sense independent from the particulars. In this fashion they are akin to individual souls, since neither souls nor form-copies will be dependent for their existence on the particular to which they temporarily belong.