2. Socrates uses the invisible and visible argument to help show the soul is immortal. Since the soul remains the same (unchanging) and can
only be grasped by the mind, it has to be immortal. Also, since the soul is visible and the change can be seen, when one dies, the body can be seen to exist only in this world. The soul, which is invisible and not composite remains the same even after death because it cannot change and therefore remains in the invisible realm; the soul is immortal.
3. Simmias’ objection at 85e-86d is against Socrates’ statement that the soul is immortal. Simmias believes that it is possible that the soul might be in the invisible realm, but he does not think that the soul exists if the body dies. Simmias uses the analogy of a harmony of a lyre. The harmony, like the soul, only exists if the lyre, like the body, exists. If there was no lyre, then there would be no harmony. In the same way, if there was no body, there would be no soul.
4. Socrates’ reply to Simmias at 92a-95a informs Simmias that he is conflicting with the view of recollection that he earlier agreed to. If Simmias believes that knowledge is recollected and not learned, then the soul would have to be immortal. Socrates explains that the soul existed before the body and therefore will exist after the body because it remains the same. He explains that the soul and body are not like the harmony and the lyre because the soul existed before the body; whereas, the harmony did not exist before the lyre.