In Husserl's phenomenology, hyletic data (hylé, "matter") are the raw sensory impressions—such as colors, sounds, or textures—provided by "impressions" before being shaped by intentional consciousness. These data are passive, non-intentional, and form the given material basis for meaningful experiences. Although present in every object, they are only accessible by an exercise of abstraction which, according to Husserl, can alter their content (as if analysis were a thermometer that alters the temperature of the water it purports to measure "neutrally").
Hyletic data are contrasted with morphé (form), the structuring activity of consciousness that organizes these impressions into coherent objects. For example, the sensory impressions of a rose’s color and shape are hyletic, while the intentional act of perceiving it as a "rose" (= noema) involves the structuring work (= noesis) of consciousness.
Since they are preconceptual, we have the classic problem of how to conceptualise the non-conceptual (Hegel, Sellars et al). Husserl himself speaks of them as literally a ‘component’ of the whole which is the object, so it is clear that he is using the mereology of the III Investigation to categorise them. The question is whether it does so from within themselves, or whether it does so by looking at them from the whole (noema) that makes them up.
So the question is whether they really, being preconceptual, can be analysed in terms of wholes and parts, being mereology a conceptual tool (I guess). I think the best way to understand them is as simple objects, because if I say that they are ‘part-of’ a whole, I am already presupposing the whole (noema) to access the parts, and therefore putting conceptual elements into them.
