My point about the spirit is that we can't be as free as we were in those days. For example, back then you could dump waste all over the place--there was no one living there, and no one to object. So we didn't need much regulation in that regard. Human nature hasn't changed, but today we're more numerous, there is no "out there" to push our problems into, and our powerful technologies, while good, also have far greater unintended/unwanted consequences. Acting in accordance with unchanged human nature means we have a far greater impact on our fellow citizens. Laws, regulation, enforcement, costs, and even insanity have grown. Perhaps the change is akin to the (supposed) change from liberal to conservative that occurs as we age--you may still have your liberal point of view from your passed youth, but now it's considered unrealistic.