Approximately: Applying ideas consistently, even outside of their usual context. Believing in the logical consequences of the things you already believe.

As opposed to: Believing some ideas, but then saying "oh no, that's completely different!" for no logical reason when someone tries to use the same idea in an unusual situation. (Dividing the world into small compartments, each governed by completely different laws, mutually unconnected.)

See e.g. Outside the Laboratory