Basically, when we're depressed our brain is using the time to restructure itself so the next time an event occurs we're ready for it.
This is a highly error-prone process, though. It is very easy for a person to develop a maladaptive pattern (clinical depression, anxiety disorders, personality disorders, etc.) because the true causes of and rational responses to the situations to which we're reacting are frequently unclear. Your brain will just take whatever explanation you give it, which is at least as likely to be a spurious and emotionally-charged one as it is well-reasoned one based on observable evidence.
What you call depression here is like the pain a little boy feels if he burns his hand on the stove--like that situation the cause (you didn't pay enough attention) and the response (pay more attention to your wife) are unambiguous--and like that situation one would have be deficient in reasoning ability (not deficient in emotion) to not learn a useful adaptation from such abundantly clear evidence.
This is important, as the chance of a maladaptive response to something increases with the ambiguity of the situation.
And so, your example is a bit simplistic and misleading. Depression is an effect: it doesn't make you learn from your mistakes, it only lets you know that one has been made. To learn a new adaptation (to some stimulus, the cause of the depression) is a process of reasoning. Common anti-depressants are not known to diminish one's ability to reason, so your claim that they would prevent one from learning from their mistakes seems unfounded. It is in fact central to psychotherapy that the patient be able to make use of their reasoning abilities to correct emotion-driven adaptations.
One would hope and expect that most patients seeking treatment for depression are people who have learned some kind of maladaptive pattern (whether they know what it is or not) that is causing them real harm in life. At that point, the idea of inhibiting that maladaptive process (breaking the self-reinforcing cycle of depression) with anti-depressants and therapy is pretty attractive and useful. Moreso than assuming that it should be tolerated simply because it's natural.
This is a highly error-prone process, though. It is very easy for a person to develop a maladaptive pattern (clinical depression, anxiety disorders, personality disorders, etc.) because the true causes of and rational responses to the situations to which we're reacting are frequently unclear. Your brain will just take whatever explanation you give it, which is at least as likely to be a spurious and emotionally-charged one as it is well-reasoned one based on observable evidence.
What you call depression here is like the pain a little boy feels if he burns his hand on the stove--like that situation the cause (you didn't pay enough attention) and the response (pay more attention to your wife) are unambiguous--and like that situation one would have be deficient in reasoning ability (not deficient in emotion) to not learn a useful adaptation from such abundantly clear evidence.
This is important, as the chance of a maladaptive response to something increases with the ambiguity of the situation.
And so, your example is a bit simplistic and misleading. Depression is an effect: it doesn't make you learn from your mistakes, it only lets you know that one has been made. To learn a new adaptation (to some stimulus, the cause of the depression) is a process of reasoning. Common anti-depressants are not known to diminish one's ability to reason, so your claim that they would prevent one from learning from their mistakes seems unfounded. It is in fact central to psychotherapy that the patient be able to make use of their reasoning abilities to correct emotion-driven adaptations.
One would hope and expect that most patients seeking treatment for depression are people who have learned some kind of maladaptive pattern (whether they know what it is or not) that is causing them real harm in life. At that point, the idea of inhibiting that maladaptive process (breaking the self-reinforcing cycle of depression) with anti-depressants and therapy is pretty attractive and useful. Moreso than assuming that it should be tolerated simply because it's natural.