I think using the term "science" is the downfall of these practices. To me, they are poetic arts - the tarot, astrology etc are all interesting poetic devices, like dreams, that we can use like Rorschach tests, to see what comes up psychologically for us. But they are obviously not exact sciences. To discount them wholesale, is like discounting Shakespeare because it is fiction - it holds many symbolic and archetypal truths. But again, it is obviously not to be taken literally or as gospel.