The third argument in Phaedo

To me the most interesting argument in Phaedo was affinity. I didn't really completely get it the first time I read it but upon further review it makes a lot of sense actually. It argues that if the body is visible and material then the soul would be immaterial and invisible. All things visible and material are temporary and subject to change where is immaterial and invisible things are permanent such as ideas ways of thinking. I feel like this is pretty convincing to me because the knowledge of how to harness fire has lasted a lot longer in human history than the first fires that we harnessed have lasted. So the soul would be the knowledge that is immortal whereas the body would be the fire that is bound to be extinguished.