Having solved a number of these problems in my youth, I tried to solve this one "by hand". But with 6 attributes of 5 properties each, the "bookkeeping" task was too difficult to deal with while trying to find a consistent solution.
It turns out that it's very easy to make an inconsistent conclusion, and it's also difficult to 'unwind' a mistake (if you can figure out where you made your mistake.) After I failed and restarted the puzzle several times in a row, I thought about one of my mantras: "Let humans do the things that humans are good at, and computers do the things that computers are good at." After all, computers are designed to good at processing large amounts of data without confusion or mistakes (assuming the software developers are competent -- and use good tools). So why not a computer program that can solve this puzzle? -- Sent from: http://forum.world.st/Pharo-Smalltalk-Users-f1310670.html
