This study of Plato's Phaedo promotes better understanding of its arguments for the soul's immortality by showing how Plato intended them, not as proofs, but as properly dialectical arguments functioning in accordance with the method of hypothesis. Unlike the argument for the soul's immortality in the Phaedrus, which does seem intended as a proof, the Phaedo arguments are proceeding toward the first principles that could serve as the basis for a proof - the most important being an account of the soul's own essential nature. This study attends to the substantial progress the Phaedo makes toward such an account. It also considers Socrates' epistemic situation in the dialogue and the problem of whether his confidence in the face of death is misplaced if his arguments have not been proofs before considering how the concluding myth draws together several of the dialogue's main themes.