Frede, Dorothea, "The Final Proof of the Immortality of the Soul in Plato's Phaedo 102a – 107a," Phronesis, Vol. 23, No. 1 (1978), pp. 27-41.

Excerpt:

Among the arguments presented by Socrates as proofs for the everlastingness of the human soul the last one has greatly puzzled philosophers because it seems that, in opposition to the earlier arguments, Plato considered this last argument conclusive.

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