There are e.g. some theories that it could be an evolutionary strategy.
> Another reason depression is thought to be a pathology is that key symptoms, such as loss of interest in virtually all activities, are extremely costly to the sufferer. Biologists and economists have proposed, however, that signals with inherent costs can credibly signal information when there are conflicts of interest. In the wake of a serious negative life event, such as those that have been implicated in depression (e.g., death, divorce), "cheap" signals of need, such as crying, might not be believed when social partners have conflicts of interest.
It could also be the degenerate case of something good. E.g. feeling withdrawn and unmotivated can be good sometimes - it can tell you something is wrong. Depression is like an extreme version of that. Maybe its the brain taking things too far and getting stuck in a bad state or something.
I dont know, IANAD, but it sounds mildly plausible.
Resilience, endurance, learning to overcome adversity, learning to overcome yourself, learning to be self-aware, thinking "differently". I could think of dozens of other reasons. No?
I'm not sure these are good examples, but depressive realism is a pretty legit hypothesis about a potential evolutionary benefit. There's also some hypotheses about energy expenditure - doing nothing is sometimes the right move, although that would have been more important a long time ago than now.
These sort of ideas are hard to evaluate definitively, but I do think it is plausible that mild depression had/to some extent may still have benefits. Of course certain traits can be taken too far though, and when viewed through that lens it is hard to understand how they could be beneficial at all. One could say a similar thing about Autism-like traits.
Depression affects everyone differently. But it does not mean a constant unending, it can come and go and those peaks and valleys lead to what I'm talking about.
> Another reason depression is thought to be a pathology is that key symptoms, such as loss of interest in virtually all activities, are extremely costly to the sufferer. Biologists and economists have proposed, however, that signals with inherent costs can credibly signal information when there are conflicts of interest. In the wake of a serious negative life event, such as those that have been implicated in depression (e.g., death, divorce), "cheap" signals of need, such as crying, might not be believed when social partners have conflicts of interest.
https://en.wikipedia.org/wiki/Evolutionary_approaches_to_dep...