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S = k. log W

"The math is easy."

Is it? Good for you. I'm very proud of you.

Not for me it isn't. Math is never easy.

I sometimes wonder if it was because a beloved high school math teacher died in the middle of a semester just as we were getting into the nitty-gritty of trigonometry. (I had been doing well up to that point... but went on to fail trig several times over the next few years of high school and college. Never made it to calculus. Because fuck logarithms. If you want to say 138 then say 138, don't say 4 log 16 or whatever.) But I think it's much more likely: I just suck at math.

I need to think it all through... very carefully... frequently a few times to make sure I'm thinking it through properly. I check my work on my phone to make sure I'm multiplying where it's called for or dividing when it's called for or whatnot. And that the number that comes out makes any sense at all.

If I'm trying to do it in my head I DEFINITELY need to think it through a few times. Which takes time. Which I may or may not actually have.

So, instead of trying to do the math on the fly, I keep laminated sheets in my wetnotes of frequently used numbers: gas matching, recalculation of thirds, RMV intervals, etc... all in imperial and metric... stuff I can pull out a sheet and see the number I've confirmed from the safety of excel in my living room.

Sometimes, if I'm bored on long, monotonous passages of cave, I will run through some of those familiar equations because I think it will make me better at them somehow. I don't know that it works, but we all need a hobby, eh?

Even "simple" algebra... fuck, even "simple" mathematics sometimes stump me. To the point where I have to give up and revisit after an emotional siesta.

I was recently reminded of a study where a championship chess player was pitted against a club player. Someone they would have soundly whooped in minutes on the surface... but there was a twist: the champion was under pressure (literally - in a hyperbaric chamber which which created the narcosis equal to {get this} 2ATA) while the club player was at ambient surface.

The champion kept losing. Inhibited at only 30 feet.

Not being interested in chess I wouldn't stand a chance. Not being adept with math I can do it, but I'm not going to be super on-point. Even at only 30 feet.

"The math is easy."

I'm so glad for you.

You know what's easy for me?

Do you want a 2000 word essay on how there is a direct correlation between Richard III's loss at Bosworth Field and the fact that drunken Englishmen "could murder a curry" today because of the Protestant suppression of good food during the civil war? I could knock that out in an hour; easy. Wouldn't need to look at Wikipedia once. (OK, maybe an hour and a half. And I might need to check Wikipedia once for what month they cut Charles' head off.)

I once wrote a paper for a 400-level university class on Milton about how John Calvin was absolutely right and that free will of humanity doesn't exist anywhere in Paradise Lost. My main proof was that God doesn't go to cockfights because he would fuck up the odds.

It was 40 pages long. I wrote it in one night. (And only got an A- I was pissed.)

That is easy to me.

Math is not.

But here's the nice thing... for me anyway...

Dive computers exist. And are are reliable. And robust. And small. And affordable.

"You can just do the math in your head.

No, brah - YOU can do the math in your head. I can do it right here on my couch with a calculator a few times so that I know what everything is supposed to look like. Then I can get in the water and do the dive as I expect it to look.

Plan your dive, dive your plan and all that.

Truth is that now, after a couple thousand dives, I can spitball things pretty well. I know what to expect and could probably pull a deco schedule from the back of a cornucopia of experience.. or do a bunch of math on the fly that would be close enough for the inaccurate science of decompression physiology. If both my full-function computers fail.

NOTE: I am certainly not suggesting that folks simply do whatever your computer tells you.

That's down a very, very bad path. KNOW the math. Do it a bunch. If you're bad at it, do it when you're bored on your couch to try to firm it up in your head or do it during deco hangs (or dull passages) to fix it more securely in your mind. I can obviously show you how... but hell, you might even be better at it than me.

And hats off to you if you are mathematically inclined. You'll be much more adept and recognising just why your computer is telling you what it is.

Now write a sonnet. At depth. After you've had a catastrophic failure to your breathing gas supply. As if your life depends on it. Because it does.

Or... if you're allowed to have a wrist-worn device to write one for you... which would you prefer?

You could substitute "sketch a profile of Harriet Tubman" or "compose a short piece for the french horn" or "choreograph an interpretive dance about the whaleboat Essex." Or any other number of things that some people are good at and other people aren't.

But if you are the sort that's good at it, don't fucking lie that "it's easy."

I'm now going to spend the rest of the night imagining what a ballet about the Essex would look like.

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1 Comment

Ian Combs
Ian Combs
Feb 27, 2021

I feel dumb even bringing this up because it's probably a trick you already know, but just in case it's not... I a hard time with laminated papers leaking through so I started printing on these, instead of laminating regular paper:

Also works well for documents you're not necessarily taking down on the dive with you but might get splashed with rain, or seaspray on a boat. Stuff like emergency plans and phone numbers.

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