We dismiss it as absurd: How would such a random thing as birthdate affect anything? (There is some idea it has to with how stars line up, which strikes us as laughable).
I will not argue for astrology. But I will point out: One’s birthdate is not “random” in the sense of lottery numbers or “coin flips”, but is almost always ~9-months after conception.
Two things I recently read suggest that, in some animals, conditions of conception matter, a lot, for the character of the new creature.
1.) In alligators, temperature of the nest determines the sex of offspring. (A nest above 90-F will produce a male, any cooler will produce a female).
2.) In certain butterflies in the tropics, the nature of the ornate patterns they develop on their wings are determined by “larval rearing temperature”, not genetics as such. [link].
Consider: Is it possible that the temperature of the surroundings of the human womb at conception, and during pregnancy, could affect the child in ways similar to what astrology claims, as seen in these other creatures? Yes, we are warm-blooded. But is it really so impossible?
Another possibility: Perhaps a spring conception is ideal for the human condition, which gave rise to European notions that spring and love go hand in hand. Are people born in December, January, February [9-months after "Spring"] superior to the rest of us?)
Even if any of this is true, it would not line up with astrology’s hard line on significance of birthdates (implicitly) everywhere: After all, some places have no seasons, some places have “wet” vs. “dry” seasons, others have wild-temp-swings in the year, others milder swings, and southern-hemisphere-ites have opposite seasons as northerners.
Anyway, modern people are not exposed to the elements very much, anymore. So is astrology “over”?