There’s foil in my wallet

But I’m not crazy. The foil is only there to block the scanners. The bank sent out the new credit card a while ago, and it has a chip in it. After reading about the potential risks, it seemed like some shielding wouldn’t hurt anything. But how to know if the shielding worked?

At one work site, I get access to the facility by putting my id card against a scanner. This works even if I just hold my wallet up to the scanner. This seems like a reasonable basis for testing. The first thing I put in my wallet was a piece of what seemed to be metalized paper from a coffee package. Holding up my wallet still activated the door, so a coffee bag probably will not block the scanners the men in black would carry if there were men in black following me.

Next time I went out to that site, I folded up four layers of regular aluminum foil and put that in my wallet. The scanner didn’t work. A week or so later I tried it again, and this time scanner did read my card through the foil. Thinking it might be because the foil had compressed, I opened up the foil and interleaved a piece of paper. My knowledge of electricity and magnetism is close to the cargo-cult level, you see. Anyway, this seemed to work, but I’ll test it again from time to time.

If I come across some sheet copper I’ll try that too. A couple of business-card size pieces of copper with the Lord’s Prayer engraved on it would probably excite less interest than a packet of aluminum foil.

Pointless exercise

Randomizing a deck of cards

Shuffling a deck of cards is a relatively poor way to randomize. It can take surprisingly many passes to completely randomize the deck, more than people use in a game. It’s possible to intentionally or unintentionally fail. The best way to randomize cards might be to spread them all out, mix them around, reassemble the deck, and repeat several times. People don’t typically do this.

It might be interesting to randomize a deck by throwing dice to order the cards. I wonder if bridge players would notice, or if it would change their play. You could say (and I would agree) that making up the deck is part of the game; that there are rules for making up the deck; and that rolling dice and looking up the corresponding cards isn’t part of the game. Anyway, a thoroughly randomized deck would be detectable through statistical analysis, and I suspect it would affect the game. The players would notice that things seemed to be going oddly.

On a big table, lay out the cards, with jokers, in rows of nine. The first die determines which of the six rows to choose. The second die could determine from what position in the row to start counting, and the third die the number to count off to choose the card. Or you could make a look-up table for three dice, following Diceware’s example.

You could set up a deck like this, and carry it in your pocket. Just in case.

The idiot

Who is the idiot with a clipboard? I don’t know. The real problem is that he’s almost certainly not an idiot, but a really smart guy.

There is a particular kind of irrational behavior that seems to be part of human or organizational nature. That the people involved are serious, capable professionals in positions of significant responsibility does not make a difference. Here are some fictionalized but truthy dialogues:

Serious Responsible Man who should know what he’s doing: “Hey Mister Wizard, thanks for coming over.”

Young Wizard: “No problem; what’s up?”

SRM: “This package might contain an infernal engine of enormous destructive power.”

YW: “Okay, I’ll take a look. You’ll need to evacuate this floor, and the floors above and below.”

SRM: “Oh, we don’t want to do that.”

YW: “?”

SRM: “It’s probably just the new filing cabinet.”

YW: “Okay, well, call if you need…”

SRM: “Wait, where are you going? Aren’t you going to open it?”

YW: “What for?”

SRM: “It might be an infernal engine of enormous destructive power!”

YW: “Then evacuate the floors like I said.”

SRM: “We don’t want to do that.”

YW: “Then open it yourself.”

SRM: “But you’re the wizard!”

YW: “Then take my advice; evacuate the floors!”

SRM: “But…”

You get the point. Examples abound. Here’s another:

Not a rocket scientist: “Why are you wearing Full Impermeable double-layer Armor, plus 2 Against Lethal Miasma?”

A real rocket scientist: “The area may be contaminated with a class IV lethal miasma!”

NARS: “Then why are you not wearing the Helm of Respiratory Protection?”

ARRS: “It makes me feel like I’m suffocating, and there’s probably not any contamination.”

NARS: “Then take off the armor.”

ARRS: “There might be contamination!”

NARS: “Then put on your Helm of Respiratory Protection!”

et cetera

But of course the military is not subject to this kind of irrationality, right? So one would ever see, for instance, an experienced senior NCO walking around in, for example, poison ivy, buck naked except for a gas mask, carrying a scrub brush and a bucket of, say, calamine lotion. But if you ever do see such a thing, the line to take is not that it’s pointless to wear a gas mask while walking around naked in poison ivy, but that it’s inappropriate for a senior NCO to do cleanup. That’s a more effective argument.