Before World War 1 and 2, humanity's technology was pretty primitive compared to today and that was just around 100 years ago. Those two wars contributed hugely to advancing technology. So if a Third World War were to happen, technology would advance again and who knows how it would impact society. Many many diseases could be cured, humans may have better space travel and humans could avoid extinction if one day a asteroid were to hit the Earth and cause mass extinction.
As long as nuclear weapons aren't involved, a Third World War should be highly beneficial to humanity as a whole.
Those who say that nuclear weapons would be used are kidding themselves. The idea of MAD (Mutually Assured Destruction) during the cold war was based off of the idea that "whoever shoots first, dies second." Nobody would be stupid enough to involve nukes.
A world war would be incredibly beneficial to humanity as it would seriously increase our combat capabilities and especially our medical capabilities. It would make us better prepared for the future.
It would cause tremendous suffering and death for what? An improved technology? There are other ways to ensure rapid technological advancements. The space race and the power of competition. NASA and spin-off technologies. Go back to the Pax Romana. The relative peace of that time saw prosperity and progress and so war is not the only way to improve things.
Mistakes can happen; perhaps events can escalate to a point when even the most rational of leaders can find no other way out of what they must do. As long as there is still the possibility of using nuclear weapons as a threat to other countries, or relying on it as backup, no one should count on others to keep a reasonable and cool head, and never use what they have at their disposal. Misunderstandings are also easy to arise. (Or there may rise again another leader who won't stop until they achieve what they want)
Yes, it might increase our medical capabilities, or technology, but it would be at the expense of millions of lives, and we would basically be trading them for technology; technology that may or may not actually be beneficial to the human race in the long run (ie. Inventions such as the nuclear bomb). Furthermore, we would only be focused on developing weapons or defense systems that would help us win the war; we wouldn't have any need of increasing research in medicine unless it was used to harm others.
Sure tech rapidly advances during war but in a world War there wouldn't be anything left for the tech discovered. The environment would be wrecked and the world would plunge into chaos. If you mean good for humanity as in going exctint yes it is good I guess. Nukes never have a good endgame
Einstein famously said that he knew not what World War 3 would be fought with but World War 4 would be fought with sticks and stones.
A world war 3 would involve nuclear weapons. Don't even kid yourself about that one. We don't need another world war. We should just put more funding into research instead and then we'll see technological advance.