Phaedo
Socrates offers four arguments for the soul's immortality:The scene is set in Phlius where Echecrates who, meeting Phaedo, asks for news about the last days of Socrates. Phaedo explains why a delay occurred between his trial and his death, and describes the scene in a prison at Athens on the final day, naming those present. He tells how he had visited Socrates early in the morning with the others. Socrates' wife Xanthippe was there, but was very distressed and Socrates asked that she be taken away. Socrates' relates how, bidden by a recurring dream to "make and cultivate music", he wrote a hymn and then began writing poetry based on Aesop's Fables.
Leon of Salamis
In the "Apology", Plato's Socrates argues that he fears committing injustice more than he fears death. In support of that claim, he cites two incidents in which he, at great personal risk, disobeyed unjust commands of the Athenian government. One of those orders was for him to arrest Leon of Salamis and bring him to the Thirty for execution:
When the oligarchy was established, the Thirty summoned me to the Hall, along with four others, and ordered us to bring Leon from Salamis, that he might be executed. They gave many other orders to many people, in order to implicate as many as possible in their [i.e., the Thirty's] guilt. Then I showed again, not in words but in action, that, if it's not crude of me to say so, death is something I couldn't care less about, but that my whole concern is not to do anything unjust or impious. That government, as powerful as it was, did not frighten me into any wrongdoing. When we left the Hall, the other four went to Salamis and brought in Leon, but I went home. I might have been put to death for this, had not the government fallen shortly afterwards. ("Apology" 32c–d)
From these texts, it is clear that Leon of Salamis had an honorable reputation, he was put to death by the Thirty, and his execution was publicly recognized as unjust and unwarranted. But this leaves open the question of who Leon was.