Great explanation by Dane Rudhyar:
http://www.khaldea.com/rudhyar/astroarticles/starvictim.shtml
Must You Be The Victim Of Your Stars?
Do we really have "free" will, "free" choice? What provides the data for our value judgments on which crucial decisions — free choices — are based? Beyond lies the still deeper problem: When a person says, "I, Mr. So-and-So, am making this decision," what within him leads to the choice?
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The great 16th Century occultist Paracelsus said, "Whatever the stars can do we can do ourselves, because the wisdom which we obtain from God overpower the heavens and rules over the stars . . . Man's soul is made up of the same elements as the stars; but as the wisdom of the Supreme guides the motions of the stars, so the reason of man rules the influences which rotate and circulate in his soul." …..
In the end the only true free will is the will to destiny and the really free decisions are those which are not "made" because they are so evident and necessary they might be said to make themselves. The freedom we have is to choose to be free and to remain so. We are born at a definite place and time in the vast environment of our solar system and the total galaxy. This place-time equation, of which the birth chart is the symbol or signature, shows what the human being potentially is as a whole, person. What would be the sense, of fighting destiny, willing to be what one is not?