The scientific method is very good a knowing some things, but it can be an impediment to knowing other things. Suppose, for instance, a gentleman is attracted to a certain lady and wishes to become better acquainted with her. Can he achieve this by measuring her, taking her temperature and subjecting her to a CAT scan? Not only will these operations fail to tell him what he really wants to know, but they are likely to so annoy the object of his inquiry that she stops returning his calls.
What he really wishes to know – the intimate secrets of her body and soul – can only be learned if he ceases to be objective. She will entrust her secrets to him only if he displays a clear bias in her favour. And the more exclusive his knowledge of her – that is, the less it can be confirmed by any observer besides himself – the more precious it is to him. The alchemist would argue that all natural phenomena have something in common with the lady.
They unfold some of their secrets to objective, scientific inquiry while bestowing others only on the subjective observer. The soul of a thing – whether animal, vegetable, or mineral – reveals itself only in active relationship to another soul.
Catherine MacCoun, On Becoming an Alchemist