4.0412 On the same grounds, the idealist explanation of seeing spatial relations by reference to “spatial spectacles” is inadequate because it cannot explain the multiplicity of these relations.

The idealist sounds rather Kantian here, at least on one popular reading of Kant. Black (p. 177) quotes Russell’s “Philosophical Importance” p. 491 saying that “The categories of Kant are the coloured spectacles of the mind,” but adds that Wittgenstein might have been thinking of Meinong or Husserl rather than Kant.

What is the multiplicity of spatial relations? Perhaps W’s general idea here and in 4.0411 is that what is general cannot be reduced to a single (or simple?) formula or explanation without distortion or implicit generailty.