The whole point of this phrase is to give us pause as we consider how to use these massive powers. We clearly have the ability to effect these changes, but your

The whole point of this phrase is to give us pause as we consider how to use these massive powers. We clearly have the ability to effect these changes, but your seeming confidence in our ability to easily solve massive problems only reinforces how important our humility is. Case in point, we accidentally dumped millions of gallons of oil into the ocean, causing a huge mess. One solution, has been using chemicals to disperse the oil, but now after trying that strategy for a bit, we are scaling back its use for fear of causing more problems. These systems we are trying to change a monstrously large and complicated and we don't understand them completely enough to be able to know the concequences of our actions. That is why we must be cautious when "playing God" I mean, it is hard enough to change pieces of an OS without having unintended consequences, and that is a system entirely of our own creation.