Thomas Reid famously claimed that our perceptual experiences reveal what primary qualities are in themselves, while providing us with only an obscure notion of secondary qualities. I maintain that this claim is largely correct and that, consequently, any adequate theory of perception must explain the fact that perceptual experiences provide significantly less insight into the nature of secondary qualities than into the nature of primary qualities. I maintain that neither naïve realism nor the standard Russellian variety of the content view can provide a satisfying explanation; instead, in order to provide a satisfying explanation, we must posit that perceptual experiences represent properties via Fregean modes of presentation. Further, I maintain that we must depart from the standard Fregean variety of the content view in two important respects. First, the relevant modes of presentation must be characterized without appealing to causal relations between perceptual experiences and perceived properties; and second, we must posit that primary and secondary qualities are represented via modes of presentation of different kinds. The resulting view is that primary qualities are represented via perceptual modes of presentation analogous to highly detailed descriptions, while secondary qualities are represented via perceptual modes of presentation analogous to impoverished descriptions.

托马斯·里德（Thomas Reid）有句名言：我们的感知体验揭示了主要品质本身，同时只为我们提供了次要品质的模糊概念。我认为这种说法在很大程度上是正确的，因此，任何适当的知觉理论都必须解释这样一个事实：知觉经验对次要品质的本质提供的洞察力明显少于对主要品质本质的洞察力。我认为，无论是朴素实在论还是标准的罗素式内容观都无法提供令人满意的解释。相反，为了提供令人满意的解释，我们必须假设感知体验通过弗雷格的呈现模式来表示属性。此外，我认为我们必须在两个重要方面背离标准的弗雷格式内容观。首先，必须描述相关的呈现模式，而不诉诸感知体验和感知属性之间的因果关系；其次，我们必须假定主要品质和次要品质是通过不同类型的呈现方式来表现的。由此产生的观点是，主要品质是通过类似于高度详细描述的感知呈现模式来表示的，而次要品质是通过类似于贫乏描述的感知呈现模式来表示的。