When do you think the quality of life on Earth peaked?

Since I’ve only been around for a small portion of it thus far it’s kind of hard to say.

The decline began at the iron age.

Most people in the world today has a far better life than only 50 years ago.

I don't think humanity really changes.  500 years ago, people gathered around the village square to watch their convicted neighbors getting their heads chopped off.  To me, this is barbaric and horrifying and unthinkable.  But there are things about life today that I think are just as gross.  I just think that there is always a sort of trade off in flux. 

Sometimes "quality of life on Earth" might be perceived as "best" during the era of one's childhood.   For example, I will always be partial to the 70s, just as my parents are very vocal about how life was never better than in the 1950s.   It also depends on who you ask.  I think so-called "liberals" are more apt to think that the best is yet to come, while their so-called "conservative" counterparts are less likely to be so optimistic.   It's very difficult to be objective about this topic.

Also, it depends on what you mean by quality.   Quality of health care and longevity and technology are valid considerations, but then progress in the quality of technology could also be considered not always a good thing, and that's valid, too.   And I enjoy my conveniences as much as the next person, but to what ultimate effect.   I read once that the one single invention of the 20th century that changed Americans' behavior more than any other single thing was air-conditioning.  Makes absolute perfect sense.  It made being inside much more pleasant during the warmer months.   And I don't think too many people would rather go back in time and give this up.   Those stiflingly hot months where it was almost impossible to sleep through the night.  But one trade off here is that it has made us a more sedentary society, more comfortable and more complacent, perhaps, but also people started staying inside more often and technology and labor changed and maybe people even started getting lazier by comparison.  And people started to get more and more interested in technology and its possibilities for making life easier, more comfortable.  It has a trickle down effect.   

People say technology is good, but I see young people becoming totally addicted to their smart phones, living for their own hand held computer no bigger than a deck of cards.   I cherish the fact that my oldest friendships still involve a decent amount of time actually hanging out in the same physical space with each other, or at least talking on the phone.   And do people still actually sit down and write letters to one another?  The act/art of letter-writing involves a certain degree of dedication and thoughtfulness and caring that sending off LOLs just does not.  And who really has 1,500 friends?   Well, I know a lot of people who say they do, but I sure as heck would never make this a personal goal.  (I have always thought that if a person can say they have six good friends, then this is a wonderful thing, maybe ideal.) 

Then again, I cannot imagine a life where there didn't seem to be much else beyond work, eat, sleep, war, sex and religion.   That seems a very dark and bleak existence.

So, my answer to your question would either be 1959 (the year the super pretty, soft, colorful, cozy, carefree and fluffy movie, "Pillow Talk", was released) or 1977, the year that my three favorite tv shows, "Columbo", "Charlie's Angels" and "The Mary Tyler Moore Show" were all on prime time.)    

Kind of kidding, kind of not.  I think times change, but people or humanity not as much, not at all or just not in the same way.   And, if the ultimate goal for humans is perpetuation of the species (and maybe it is, I cannot say), then I guess times continue to get better as life expectancy continues to grow.   

Well, I sort of agree with you on the part in italics.   But this is where the objective vs. the subjective factor into the matter.  Depression and suicide are, ultimately, very personal things.  And I don't have any statistics, but I am thinking that faith and religion and the "fear of God" had a lot more presence in the lives of people 500 years ago than they do today.  And I bet that depression and anxiety and suicidal tendencies were looked at with a whole lot less respect (for lack of a better word) back then, than they are today.   For better or for worse is not for me to say.

I had an acquaintance from Vietnam, and once she said, in a straightforward, non-judgmental manner, that the whole notion of psychotherapy was pretty much exclusively a Western notion, way of thinking and that it essentially was a very narcissistic and self-centered thing to indulge in.  I've spent my time with therapists and could have been offended, but, ultimately, I couldn't help but agree with what she said, or at the very least I appreciated and respected this way of looking at therapy, and by extension depression and anxiety and any self-destructive behavior. 

And I don't mean this in a heartless or judgmental way at all, but suicide really is the ultimate act of self-absorption.   So maybe people are just more self-absorbed than they were, even 50 years ago. 

 Also, look at how everything in our consumer culture is geared toward giving us more pleasure, more conveniences, more excess.  (Does civilization really need the deep friend Twinkie?)  And this has the inevitable and not very attractive result of making us more self-centered, and, somewhat paradoxically, more unhappy.  Just look at the sheer quantity of distractions we have today.  Like the number of channels to choose from on tv can be over 500!!! When I was a kid in the 70s, I lived in a small town outside of Indianapolis and I believe we had 7 or 8 channels to choose from, not including HBO. And programming shut down at 3:00 am.  And the target audience seems to be getting younger and younger, and young people are just not going to have the same level of self-awareness to be making the smarter, more responsible decisions about the bigger picture.   

And there is something that is, I suppose, meant to be comforting (for people of a certain age, at any rate), but is also just as disturbing about a saying/attitude that entered into the national consciousness a few years back, re: "sixty is the new thirty".  This kind of thinking appeals to man's biggest fear which is fear of death, which rests on the toes of our fears of getting older, then fear of maturity, fear of accepting responsibility, fear of hard work, fear of not having Mom and Dad to take care of us, fear of falling down and skinning your knee, blah, blah, it all comes from the exact same place. 

I don't know if you've ever seen a movie from the 1930s.   But a movie character from a movie made in 1930 who was supposed to be about 18 years old, (a young person, right?) - usually looked about 35-40 years old.  I may be exaggerating a little, but not very much.  Life was harder then, people aged more quickly then, people didn't live as long, etc., and it is a completely intuitive thing for human beings to want to be young and to put aging off and to live to a longer age and to not have to work quite so hard and to be able to get by with immature and self-centered behavior and to be able to enjoy all the creature comforts that are out there.  It would be only the individual with the extraordinary inner constitution to reject these comforts because of their "un-natural" nature, for lack of a better word.

At the same time, I bet even Moses himself would have preferred a Big Mac and fries and a Coke for dinner over roots and berries and river water. (Why do you think they call it a Happy Meal?)   It's all relative.  

Started to decline around the same time you started posting here, brah.

<smirk>

j/k