> The "we don't understand" is not true anymore. The reality is that there are so many factors affecting a certain visible outcome that it's hard to specify a r

> The "we don't understand" is not true anymore. The reality is that there are so many factors affecting a certain visible outcome that it's hard to specify a root cause. That sounds like "we don't understand" except now we slightly better understand how little we understand. We don't even know how Tylenol works.