With all due, etc, my temper degenerates into uncontrollable irrationality or unexpected optimism depending on where I am in my cycle. I wouldn't necessarily discount the effect of hormones. Especially as for those of us lucky enough to have FUCKED endocrine systems, they pretty much dictate our lives; The world may be fucked up, but whether I am mildly annoyed by this or screaming at inanimate objects depends a good deal more on my ovaries, the weather, and the time of day than it does on the actual events involved.