[mlochbaum]

The relationship is interesting. Chris is trying to find a minimal set of functions good enough to derive the rest (a worthwhile goal, and it mentions at the bottom that I did something similar in BQN). Part of my current thinking about primitives is that it's not important how many there are, more that each represents a coherent simple concept. But primitives that are too similar can cause problems for memory and maybe intuition.

[moonchild]

What is your opinion of the j. primitive in j?

[mlochbaum]

It makes complete sense and I'll add the same thing to BQN if it gets complex numbers (this is why ⍳ is on the keyboard, but other options could be better).