So my susceptibility to depressive and manic states is a moral problem? How so? What does that actually even mean? I don't take it as Szasz saying I'm immoral for getting depressed, but that just leaves me completely flummoxed to understand what he does mean. And he merely asserts it without explanation.
Then, "whereas in modern medicine new diseases were discovered, in modern psychiatry they were invented."
Maybe so, but there's an obvious alternative, which is that real problems, whether appropriately called diseases or not, were identified rather than invented, which suggests they have no basis in reality. Even if some were totally made up, that's not proof they all were. It's not logically impossible that he's right, but again he just asserts without supporting argument.
At least in his writing, Szasz is not at all a rigorous thinker.