To quote a friend of mine in a discussion about maps over interstellar routes sighted by people who have been kidnapped by aliens: “Give me a star map and I will show you Mickey Mouse”.
Astrology in detail and anything relating to the moment of conception seems unlikely to be fodder for a coherent theory, and hence tricky to test (and I’ll side with Popper on whether such predictions are meaningful or not).
However, part of my undergrad degree at a well-known English university (which has an extreme attitude that all psychology should be rigorously scientific… even down to naming itself the ‘Experimental Psychology’ department, and starting the course off with an entire term of statistical methods) involved developmental psychology.
From the clear importance of environment in the early stages of a child’s development (as in months), I’ve always considered it possible that personality could be coloured by the season and prevailing light / dark conditions of the child’s first three months of life outside the womb. And though I didn’t either do the experiment or follow up further, I’d be fascinated to find out if someone had, because I reckon the results would be statistically significant.
Latitude would be a critical factor, since shorter days both affect the body’s chemistry (vitamin D production at the least) and the social factors of heat vs cold (i.e. the ‘miserable’ months as opposed to the sunny ones) would have to be factored in.
Cultural differences could pose a problem, since cultures have their own ways of dealing with the misery of midwinter (slinging a big festival around the winter solstice is a good 'un and will skew the results). But these are broad and should be visible in the data.
The plural of anecdote is not data, but I was born in October and am naturally pessimistic and gloomy. My girlfriend was born in June and is naturally optimistic.
I’d love to see a proper controlled experiment done using very basic personality measures, correlated against month of birth (corrected for latitude). I think the results would be significant.
However, astrology… it’s too detailed to be falsifiable and hence I reject it. But I can see where the idea came from, and over human lifetime scales, should even correct itself for latitude (though the extreme short days / nights of high latitude populations would make light duration more critical than astrology…)
That’s a good question. Do people living in northern Scandinavia have a statistically lower or larger propensity to believe astrology than, say, southern English?