General knowledge is unpredictable. If you want to treat human diseases, explore the natural world, because a huge portion of the pharmacopea we have is in some way directly derived from general knowledge - the taxane family is derived from yew, sometimes when you explore easter island you find rapamycin, penicillin is a very old story of accidental primary research, it goes on and on. And many of the synthetics we have now are adaptations of an older drug with negative side effects to manage the side effects.