I'm searching for an idiom to use to say briefly that two different outcomes may represent different sides of the same underlying phenomenon. I would use it in the topic of a chapter. These two outcomes are not necessarily good or bad, which is why I abandoned the idiom "two sides of the same coin" since I learned that it refers to something positive and negative.
For example, I could say something like "Threatening situations provoke different reactions - are flight and fight just different outcomes/reactions of/to the same thing?". The example here is maybe not the best, but I hope you get the point (because flight and fight are different reactions to the same thing, but I'm trying to theoretically draw together something that is not so obvious).
Looking forward to hearing your witty suggestions! :)