No. Not the Thinker you’re thinking of. The Thinker, by Susan Villas Lewis.
Susan designs under the name Stay Toasty and her patterns are available for download on Ravelry. Here’s another look at one of my new favorite hats. And then a view from the front and from the top because this hat is great any which way you look at it.
My Thinker is knit in that new favorite yarn of mine: Plymouth Yarn Worsted Merino Superwash. Every stitch pops!
The Thinker pattern is clearly and intelligently written. I’ve found no errors and see none reported on Ravelry. It’s sized from newborn to adult large. Many knitters write that they found they couldn’t knit just one. And I couldn’t either. This is Isaac’s version, knit in the same yarn.