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Yeah, for professional robotics you just accept that this is the world we live in. But for learning and hobbyist stuff, it's better to play with simple hardware and build the things that ROS is ultimately abstracting over before you try to pick up ROS.

I've seen people get sucked into ROS + simulation who end up never touching real robots. Which is fine if that's what you want to play with, but it's debatable if "ROS + sim" alone is even "robotics."

The thing that most people don't appreciate is that ROS was co-designed with the PR2, which had a very idiosyncratic architecture: two separate computers in the base, ethercat for comms, not at all modular, and very high end parts (for 2010ish). Most of the weirdness of ROS looks less weird in light of the design of the PR2, and most of the evolution of ROS was to get away from the PR2 model for more general platforms.

If you were in robotics prior to 2010, you probably would have used something called Player/Stage (by some of the same people who developed ROS). Believe it or not, another big motivation for ROS was solving the (many) problems that popped up as people tried to get Player/Stage running with robots like the Pioneer 3-DX.

Get an arduino kit and learn a little electronics. The kit likely comes with a brushed motor and a servo. Learn how motors works and how to write code to make motors spin. Then get a stepper motor and an arduino-compatible motor shield or CNC shield and spend some time getting multiple motors to move. Once you understand those basics, you can hook motors together in a rigid frame and you have a robot (2 motors with wheels is mobile, 3 or 4 motors with links is an arm). The kit will also come with some simple sensors which you can use to do things like measure light and distance, which you can use to start playing with feedback control (look up Braitenberg vehicles for a project idea).

Seconding all the people who said avoid ROS - it's not worth the effort for hobby-level stuff. It's barely worth the effort for "professional" robotics.

Also don't worry about physics too much - build your physical intuition by playing with working systems of increasing complexity.

The Stoics are explicitly mentioned in Acts of the Apostles, but I think a better way to think about it is that the framework of "Virtue" as "Conforming to your Nature" is a very useful one for understanding the gospels, as was developed extensively starting in the mid 1200s.

It's interesting that the main thinkers listed are all Roman. They're definitely the best known, but Stoicism was a Greek philosophy first and foremost, and Cleanthes, Chrysippus, etc. were more significant than any of the Romans.

Stoicism had a lot going for it, but it was also full of a lot of crazy nonsense - there's a reason you've never met a Stoic who was fully on board with Stoic natural philosophy or "physics." The logic eventually made a comeback (via Frege, possibly due to plagiarism!), and the virtue ethics got absorbed into Christian moral philosophy by about the 13th century (by way of neo-platonists who influenced Dominican philosopher theologians like Aquinas). It's not surprising that it ran out of steam.

I can imagine that a very risk averse lawyer would have pointed out the costs and uncertainties of litigation in cases like this. But if I were in their shoes and I really cared about the money, I would have pressed that lawyer to show examples where the clawback clause had been invoked since Jan 20. I'm not sure it's happened, which seems relevant to estimating the actual risk.

Interestingly, they may get more in donations than they would have from this grant, so maybe that needs to be including in the risk estimate as well...

Not a lawyer, but the NSF clause covering clawbacks is pretty specific:

> NSF reserves the right to terminate financial assistance awards and recover all funds if recipients, during the term of this award, operate any program in violation of Federal antidiscriminatory laws or engage in a prohibited boycott.

A "prohibited boycott" is apparently a legal term aimed specifically at boycotting Israel/Israeli companies, so unless PSF intended to violate federal law or do an Israel boycott, they probably weren't at risk. They mention they talked to other nonprofits, but don't mention talking to their lawyers. I would hope they did consult counsel, because it would be a shame to turn down that much money solely on the basis of word of mouth from non-attorneys.

This is fun. But the bit at the beginning about philosophy is not correct. Parmenides did not believe in what we would call essences, but really did believe that nothing ever changes (along with his fellow Eliatic philosopher Zeno, of paradox fame). The idea that change is an illusion is pretty silly, and so Plato and especially Aristotle worked out what's wrong with that and proposed the idea of _forms_ in part to account for the nature of change. Aristotle extended Plato's idea and grounded it in material reality which we observe via the senses, and that's where the concept of essence really comes from - "essence" comes from the Latin "essentia" which was coined to deal with the tricky Greek οὐσία (ousia - "being") that Aristotle uses in his discussions of change.

The Nevada Museum of Art had an exhibit last year about Picasso's ceramics, and I was amazed at how ... meh it all was. Apparently the market agrees with me, because you (yes you!) can buy a Picasso plate for just a few thousand dollars.

Pope Pius XI wrote about _subsidiarity_ as a guiding social principle:

"Just as it is gravely wrong to take from individuals what they can accomplish by their own initiative and industry and give it to the community, so also it is an injustice and at the same time a grave evil and disturbance of right order to assign to a greater and higher association what lesser and subordinate organizations can do. For every social activity ought of its very nature to furnish help to the members of the body social, and never destroy and absorb them."

Tao is observing the consequences of a society that increasingly has abandoned subsidiarity as an operating principle. (I had hoped that crypto might be able to bring subsidiarity back, but so far the opposite has happened in practice.)

This feels like the kind of popsci that's written for people who already agree with the author - there's nothing resembling an argument, or even a definition of "computation." There are nods to Church-Turing, but the leap from "every effectively calculable function is computable" to "life is a computation" is larger than anything you could fit in a book.

This is the Lean blueprint for the project, which is a human-readable "plan" more or less. The actual Lean proof is ongoing, and will probably take a few more years. Still cool though.