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Oh come on. Things fall down because matter has a property called gravity that attracts other matter, and below us is a giant earth with a lot of matter. And it

Oh come on. Things fall down because matter has a property called gravity that attracts other matter, and below us is a giant earth with a lot of matter. And it has more of a net effect on us than any other matter in the universe because gravity scales with distance and mass in that particular way. That's as darn good of an explanation of why we fall down as one could possibly give. "But why does mass have gravity?" Why does Newton have to have all the answers to every other question too? Maybe ask that and someone will answer that question in a few hundred years? He answered your original question, he didn't claim he can answer every subsequent question you think of. It's quite ridiculous to suggest Newton just tautologically concluded "things fall down because they do" just because he doesn't go on and explain the "why" of every sub-question ad infinitum.

2b3a51 1y ago
I'd just throw in that this idea of universal gravitation coupled with the laws of motion and dodgy ideas like force and momentum enabled a wide range of phenomena to be described and some predictions to be made that could be compared with observations. Yes, ideas like 'force' and 'momentum' were a bit dubious but the resulting theory was effective[1] within its domain of applicability. [1] https://en.wikipedia.org/wiki/Effective_theory https://en.wikipedia.org/wiki/Effective_theory
tralarpa 1y ago
> That's as darn good of an explanation of why we fall down as one could possibly give Well, around two hundred years later they found out that it is not a good explanation (which of course in no way diminishes Newton's achievements).
- TMEHpodcast 1y ago
  Newton’s physics is still taught and used everywhere because it’s simple and accurate enough for 99% of practical situations. Einstein’s relativity isn’t a better explanation, it just extends it to extreme conditions. NASA still uses Newtonian law to launch rockets.
sanderjd 1y ago
> That's as darn good of an explanation of why we fall down as one could possibly give. To me, the right word for this sentence is clearly "how", not "why".
layer8 1y ago
The real “why” is because energy distorts spacetime [0], and gravitational acceleration is just uniform motion through that distorted spacetime. We’re still trying to figure out why exactly energy distorts spacetime. [0] https://en.wikipedia.org/wiki/Stress%E2%80%93energy_tensor https://en.wikipedia.org/wiki/Stress%E2%80%93energy_tensor

2b3a51 1y ago

I'd just throw in that this idea of universal gravitation coupled with the laws of motion and dodgy ideas like force and momentum enabled a wide range of phenomena to be described and some predictions to be made that could be compared with observations. Yes, ideas like 'force' and 'momentum' were a bit dubious but the resulting theory was effective[1] within its domain of applicability. [1] https://en.wikipedia.org/wiki/Effective_theory https://en.wikipedia.org/wiki/Effective_theory

tralarpa 1y ago

> That's as darn good of an explanation of why we fall down as one could possibly give Well, around two hundred years later they found out that it is not a good explanation (which of course in no way diminishes Newton's achievements).

TMEHpodcast 1y ago
Newton’s physics is still taught and used everywhere because it’s simple and accurate enough for 99% of practical situations. Einstein’s relativity isn’t a better explanation, it just extends it to extreme conditions. NASA still uses Newtonian law to launch rockets.

sanderjd 1y ago

> That's as darn good of an explanation of why we fall down as one could possibly give. To me, the right word for this sentence is clearly "how", not "why".

layer8 1y ago

The real “why” is because energy distorts spacetime [0], and gravitational acceleration is just uniform motion through that distorted spacetime. We’re still trying to figure out why exactly energy distorts spacetime. [0] https://en.wikipedia.org/wiki/Stress%E2%80%93energy_tensor https://en.wikipedia.org/wiki/Stress%E2%80%93energy_tensor