# Thread: An exercise in reason, logic, and intuition

1. Originally Posted by Speakpigeon
Originally Posted by bigfield
Had three tries and couldn't solve it.

I've now read the other solutions above and realised my mistake.
Well, that probably isn't going to count because, no offense intended, I'm sure this thread somehow doesn't count you as one of "our resident philosophers and logicians".
EB
I don't worry about things like that.

2. Originally Posted by Bomb#20
Originally Posted by steve_bank
The peanut gallery spoiled the problem. I was hoping to engage our resident philosophers and logicians.
Why do you feel the peanut gallery spoiled the problem? You say it's for the intuitive and logical and philosophers -- but the only spoiled problem is the problem for graph theorists. Sure, your exercise looks like a graph theory problem; and sure, if you read it as a graph theory problem it's one of the two basic impossible-to-draw graphs that all non-planar graphs must contain; but that just makes the puzzle into a challenge to read the problem statement more carefully, and find a tricky way to solve it with intuition and logic and philosophy instead of with boring old graph theory.

Here's one of my solutions:

Draw the lines with a pencil. After step 3, use the eraser to make a gap in one of the lines you drew. Then one of the lines you draw in step 4 can go through the gap. It doesn't physically cross any line, and the problem as stated never said you can't erase lines. I'm not a lawyer, but I play one on the web.
I was looking to see how our resident logicians reasoned it out.

3. Originally Posted by steve_bank
I was looking to see how our resident logicians reasoned it out.

I tried it once, and "failed," but I didn't think I'd done anything wrong.

I concluded, therefore, that it can't be done.

4. Originally Posted by Wiploc
Originally Posted by steve_bank
I was looking to see how our resident logicians reasoned it out.

I tried it once, and "failed," but I didn't think I'd done anything wrong.

I concluded, therefore, that it can't be done.
An older cousin laid it on me when I was a kid. I actualy learned something. Concentration and perseverance.

The original kids problem was 3 houses and 3 utilities. Gas, electricity, and telephone. The solution being gas goes underground.

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