I've been recently trying to understand the concept of paramagnetism, but I feel like I'm running into 2 conflicting models. Stern–Gerlach seems to suggest that electron spins always point up or down to an incident magnetic field, regardless of their spatial orientation. Similarly, when thinking about topological insulators or electrons in the same orbital, spin is thought of as up or down without really pointing in a particular direction in x, y, z space. However, in the usual picture of paramagnetism, the dipoles of atoms and their larger magnetic domains point in 3d space, and can have any angle relative to one another (without considering ordering), not just 180 degrees. I guess I'm not seeing how the up-down-only picture of electron spin can be reconciled with the solid state picture of atomic magnetic dipoles, wherein atoms have magnetic dipoles pointing in 3d space.