"But I am not an object. I am not a noun, I am an adjective. I am the way matter behaves when it is organized in a John K Clark-ish way. At the present time only one chunk of matter in the universe behaves that way; someday that could change." -- John K Clark

That one struck particularly, nice one.

I guess I'll use this thread to post a quote from "The tale of Hodja Nasreddin" by Leonid Solovyov, translated by me. I think it fits very well with the recent sequence on diligence.

"He knew well that fate and chance never come to the aid of those who replace action with pleas and laments. He who walks conquers the road. Let his legs grow tired and weak on the way - he must crawl on his hands and knees, and then surely, he will see in the night a distant light of hot campfires, and upon approaching, will see a merchants' caravan; and this caravan will surely happen to be going the right way, and there will be a free camel, upon which the traveler will reach his destination. Meanwhile, he who sits on the road and wallows in despair - no matter how much he cries and complains - will evoke no compassion in the soulless rocks. He will die in the desert, his corpse will become meat for foul hyenas, his bones will be buried in hot sand. How many people died prematurely, and only because they didn't love life strongly enough! Hodja Nasreddin considered such a death humiliating.

"No" - said he to himself and, gritting his teeth, repeated wrathfully: "No! I won't die today! I don't want to die!""

About the book: it uses the name Hodja Nasreddin, but has little to do with him. The Nasreddin that Muslims know was a mullah. This one is a rabble-rousing vagabond who enters harems, makes life hard for corrupt officials, and has been successfully executed in every city in the Arabic world. I think that Solovjov took a Muslim hero and created a Communist hero. But that doesn't take away from the fact that the book is a masterpiece.

A man with one watch knows what time it is; a man with two watches is never sure.

This is related to something I've been thinking about lately. You may or may not be familiar with the concept of significant figures. In a nutshell, they're a way of communicating the precision of a measurement using the number of digits written. This seems to be a pretty good explanation.

Let's say we are building a robot scientist. The robot scientist has no need for significant figures; those are for puny humans. Instead, it stores measurement and uncertainty separately. One way of doing this is to store the uncertainty as ±x. Another more interesting way is to store it as the standard deviation of your measurement. This opens up an entire host of problems.

For example, let's say that the robot screws up when it's measuring something and doesn't realize it this until it measures a second time and gets something completely different. Obviously, there was some procedural error in the first measurement. Does the first completely wrong measurement contribute to the standard deviation? Isn't it possible that the second, third, fourth, and fifth measurements are also completely wrong in some way that the robot has not yet realized? Under what conditions are you allowed to "throw out" a measurement?

Obviously, there was some procedural error in the first measurement.

Obviously, there was some procedural error in the second measurement.

Obviously, things aren't as obvious as they seem.

It's not which measurement has the procedural error that matters. It's what you do when you discover it.

Alternatively, what should the robot do if it gets one measurement that's far different than all the others, and it doesn't know why?

I'm imagining the Lost in Space Robot in a lab coat. High Larryous. Danger! Danger! The second measurement was three standard deviations from the mean!