Hi!

As long-time readers of the newsletter know, I’m a fan of variant sudoku puzzles — sudoku with strange rules like thermometers, ratio dots, cages, and other things that you’re probably already confused by. Many times, I’ve mentioned and endorsed James Sinclair’s Artisanal Sudoku newsletter, and I’m going to do the same today — and then some. Because James has a book out, and I have photographic evidence that you’ll like it.

This week, I was in Manhattan and early to an event I was attending, so I stopped by Strand, a famous used book store. I went to see if they had any of my books on the shelves and they did, as seen below. And on the same shelf, next to my book (I rotated the image below), is the book I’m here to share with you today — James’ book of 150 handcrafted variant sudoku puzzles.

I didn’t buy his book because I already owned it — I preordered it when he announced it last fall. Easiest impulse buy in recent memory, too, because his puzzles are fantastic. (I didn’t buy my own book either, but it’s sitting there for $10 if you want a used copy. I considered stealthily signing it but I didn’t have a pen on me, and didn’t want to get arrested.)

But don’t take my word for it — try one of his puzzles yourself. Here’s one from this week’s newsletter, which you can play online here:

The rules:

• Regular sudoku rules apply — place the numbers 1 through 9 in the grid nine times each, so that no number repeats in any row, column, or bold-outlined 3×3 box.
• The sum of the digits inside each cage is equal to the small number in the top left corner, and digits cannot repeat within a cage.
• Those grey lines are thermometers. Digits on thermometers increase from the bulb end, and not necessarily incrementally.

Enjoy, and if you like it, consider buying James’ book. And if you’re like me, copy the pages so you don’t have to write in the book itself.

The Now I Know Week In Review

Monday: A Life-Saving Football Blooper: He got a kick (heh) out of this one, and it sent him to the hospital — thankfully.

Tuesday: A Planely Obvious Punishment: Stupid human tricks, with somewhat predictable results.

Wednesday: Why You Shouldn’t Tick off a Tiger: It may not get you right away, but that may not matter.

Thursday: The Boy and the Blue Cup: A heartwarming story.

Long Reads and Other Things

Here are a few things you may want to check out over the weekend:

1) “Inside the Quest to Mine the Bottom of the Sea” (New York Times/gift link, 11 minutes, June 2026). This is very cool, albeit controversial.

2) “How Long Does It Take to Plan a Bridge?” (Construction Physics, 6 minutes, June 2026). The “New Tappan Zee Bridge” listed here isn’t too far from me, and I felt like it took forever. But it only took five years to build plus another 13 to plan, which … OK, kind of does feel like forever. It’s not out of the norm, though.

3) “The Secret Garden of Rock-Paper-Scissors” (The Shamblog, 6 minutes, May 2026). What happens when you add more options to the classic three-option game? He did the math.

Have a great weekend, and let’s go Knicks!

Dan