Well, yes and no. We certainly know a lot more than people knew back then. We know vastly more about the cosmos, we know about atoms, we know about evolution, we know much about the brain.
We also face very different challenges than people millennia ago - we have weapons of mass destruction, more obesity than famine (in developed countries), social media, and so on.
Thus, I'd say only a small part of philosophy is still applicable and valuable today. (For example, Seneca was a Stoic, and Stoicism had much to say about physics and logic, which is pretty obsolete now, I'd say.)
There's a potential fallacy there, like thinking that old music was better, when what we still hear today is just the very best of old music.
People more than two millennia later still find what he said relevant. What is it that we have produced in the last century would meet that test ? How much of that will be due to our increased knowledge and technology ?
Knowing that physical and psychological state are linked, and that they affect each other.
We have ways of introspecting one's mind and body and understand the the "whys" of being an individual and also Human.
On that matter - my dad and my grandpa were alcoholics; and thus I have the same vice if I don’t pay attention to my motivations in life.
However knowing genetics didn’t help me understand that :)
Math is applied philosophy and theory of knowledge.
Physics is Math applied on reality.
Chemistry is applied Physics.
Biology is applied Chemistry.
I've seen Susskind convincingly (albeit shallowly) argue that more "primitive" animals understand physics and I would be surprised if it was easy to argue that animals understand mathematics without circular logic or quick and loose definitions of what math is.
Of course, I have asked many philosophical questions of myself, when understanding software. This, I've noticed, especially happens when you're crossing layers. For example, between hardware / assembly, assembly / C, C / OOP.
However, considering that we have not really come up with a language with which we can communicate with computers seamlessly, I have my doubts. Because, unless we have a language, we can't really philosophize.
This could be a problem due to the interfaces we have though. Or probably, because our interfaces with computers seem to be getting broader and richer with each generation of hardware, we haven't really been able to freeze on the language through which we communicate.
I'd argue though, that a good life is a balance between human condition and material needs. A kind of optimized frugality.
I'd bet my left pinky that people knew this earlier in life than us because our society shields us from our true selves.
Too many distractions to the point it's harmful.
Just to put forward a few recent criticisms:
#1.
This quote is a very literal example of a sort of "man up" style of prescriptive thinking which tells you to solve your behavioral problems by Being More Manly. For the vast majority of people, being told to Be A Man doesn't work to alter behavior in the long run, it discourages self esteem and offers no practical guidance. If studying mammalian behavior is any guide, this sort of advice is likely a product of a man's instinctual dominance drive. Males love to give advice because when it sounds good it helps them accrue status and cement their position in the dominance hierarchy, which increases their mating options.
We have numerous moderns alternative to Be A Man if you want to change your behaviors, the best ones are based on the past 50 years of research into how the brain works. They typically focus on understanding emotional, unconscious, or instinctual behavior and working out how to process these things more productively. Examples include cognitive behavioral therapy (and a host of similar emerging therapies), or BJ Foggs' Tiny Habits framework (which was recently shared on HN).
#2.
For a criticism of a totally different tack, Epictetus and Seneca are both operating within a rigid framework that privileges values such as efficiency, self-improvement, and accomplishment. Presumably, they see these things as the best path to happiness.
Why are these values privileged? What authority has established that any of them, including personal happiness, are important and meaningful to pursue? In the past century we've been exposed to multiple strains of existentialist, postmodernist, and nihilist thought which all emerge from the same revelation--existence fundamentally has no meaning, all value systems are human constructs, and the universe is much larger than our day to day struggles.
All our traditional values are now beset by refutations. We believed in God, but centuries of scientific progress have dispelled the evidence supporting His existence. We believed in civilization, but our largest societies went on to slaughter millions. We thought the universe revolved around us, but learned that we're ants crawling on the face of a pale blue dot, of no consequence in the cosmos to any but our own self-centered perspective.
This might all sound pretty dark, but the good news is that nothing you do is really important. The universe will remain unperturbed no matter what actions you take (or don't)! So if you're stressing about how well you live, remember that you're merely chasing fictions in a framework that someone else cooked up.
This is a modern day revelation that would never have been achieved without modern science and rationalism, and is still developing. There are as many views on how to process existence's meaninglessness as there are philosophers. To name a few: Nietschze's will to power, Camus' absurdism, Sartre's pursuit of personal freedom. Alternatively it's fine to spend your afternoon playing Xbox, no matter what your parents say.
#3,4,5++
I'm sure there are more!
I'm not really convinced by this type of reasoning. Things do matter if people care very deeply about them. If someone murdered someone close to you (to take an extreme example), would you still say that that is fine, because in the grand scheme nothing matters? You might say that you're an irrational human being, and that's why you care. But why should we take a definition of "meaningful" that is so disjoint for everyday human experience?
What would a hypothetical world look like in which life does have meaning, according to your definition? If no such world is even imaginable, then it isn't even clear what we are talking about.
Furthermore, I think some people use the supposed "meaninglessness" of life to justify passivity. If the universe is truly meaningless, then doing nothing is as meaningful as doing something traditionally considered meaningful.
Yet, people often base their behavior on their current emotional state. That is not the behavior of someone who believes in the complete meaninglessness of everything. Clearly, that person believes that his emotions matter and are a good guide to choose which actions to take. Playing Xbox on the couch or ruminating about the meaninglessness of life being good examples of this. Such actions are choices that are ultimately derived from value judgments.
If having a work ethic gets you through your day--OK, have one.
But you don't have a "better way of thinking" than someone who's lazy in any meaningful way. Nor are you more intrinsically valuable than them, outside of a very local context in time, space and culture.
Sure if I lose a loved one it's going to affect me deeply and I will grieve, but as a matter of likely fact, I will someday move on (as any good psychologist would advise). The meaning of death and its impact are not universal, merely local.
In my opinion the essential lessons are two. One is very practical. It is about humility and perspective.
The second is more esoteric. It is about freedom. The existential crisis sets you free. But like the lifelong convict who has just been released by his jailor, it remains up to you to be free.
This is an interesting idea - theoretically, there should be a possible action that "perturbs" the universe. It's a matter of scale and efficiency, so this sounds like an engineering problem rather than a philosophical one.
Gives a slight taint to the meaning of the word 'progress'.