NB/ as well as being as topic within itself, conceptual schemes can also be used as an example of non trivial, a priori knowledge if you refer to Kant's a priori, synthetic predetermined conceptual framework.
Generally, conceptual schemes are viewed as neccesary in order to make our experience intelligible. e.g. Condillac's statue receives a stream of unmediated sense date and cannot form concepts or make sense of this, he requires conceptual framework to avoid a "blooming buzzing confusion" (William James)
1. Kant's claims that the conceptual schemes are predetermined as we would have not intelligible experience at all if we had nothing to organise our sense date "thoughts without content are empty, intuitions without concepts are blind" We must have them prior to experience else we wouldn't make sense of the world, e.g. we must have category of unity - pc security system - we can distinguish between sratches/lines and letters.
-But it can be argued that such organisation comes from experience (empiricism) e.g. when I taste a dish I then categorise it as tasty or exotic in my mind.
-Because all sense data (including taste above) can be categorised in different ways, we need Kant's common concepts of space, time etc to bind sense data and give one overall unified experience e.g. link taste and smell as both are experienced spatially and casually.
-But Hume, refutes this and argues that our concept/category of causality can be known through experience by observing one event causing another event to occur and generalising through induction that this will continue to be the case e.g. billiard balls. Hume's law states that synthetic truths…