- Both use pale malts and sugar to achieve a light body, great strength, and high attenuation;
- Both downplay or eschew caramel malts to create a more candy-like sweet base;
- Both highlight hops, though of course, in tripels the balance point is in a far different place.
The goals are a little different, but not entirely. In terms of the kind of experience they're meant to produce--a reflective, special treat--they have something in common. I had a Westmalle Tripel on Friday to remind myself just how hoppy it is. Perhaps this is a personal thing, but if I had bottles of Pliny the Elder, Westmalle Tripel, a stout, a pale ale, a pilsner, and a lambic in the fridge, when I got in the mood for it, I would have a hard time deciding between the Pliny and Westmalle. They scratch the same itch.