Locke's distinction between primary and secondary qualities

From Locke's Essay on Human Understanding, Book II, Chapter 8

[じゃみっと]

Hi Simon, I hope you received my index.

[danwylie-sears]

Epistemologically, I don't see any reason to believe that an idea must be true, just because it has been wired into our development by evolution. The idea itself doesn't even have to be selected for. If a gene affecting the development of our nervous system leads to building in a false idea, but it also speeds up computation of some crucial process using empirical information, it will be selected for. So innate ideas can't possibly be a sound starting point for epistemology.

Well, not unless you postulate that they've been granted to us by an epistemology-friendly creator, as Descartes did. But in that case, it's not the innate ideas that are your starting point. It's whatever framework you shove under your theology.

On the other hand, the idea that we're born as blank slates has been conclusively refuted, empirically. So you can believe we're born as blank slates, or you can be an empiricist, but you can't have it both ways.

Then there's the dreaming thing. Consistency doesn't enable you to be sure that you're not dreaming in a way whose apparent consistency exceeds your ability to recognize consistency while dreaming. My ability to analyze stuff for consistency during regular dreams is pretty much garbage, and the same could be true of the waking world if it's another layer of dreams. But I can tell that I'm dreaming in a way that I'm nowhere near smart enough to dream up. Even if the world really is a dream, and there's some ultimate sense in which the dreamer is me, brahman is atman and all that, the dreamer definitely isn't me in any ordinary sense of what constitutes me. Maybe you're smart enough to dream up this kind of world, but I definitely am not.

Ok, a hot-button debate: pen or marker. As I understand the word, a pen applies ink from some reservoir of liquid, whether that's by dipping the tip of a quill or a metallic nib into an inkwell, or by having the reservoir of ink be inside the body of the pen. A marker, by contrast, contains no freely-flowing liquid. Its reservoir of ink is contained in a piece of porous material that's continuous with the tip. A hybrid possibility is a marking pen, which contains a reservoir of free-flowing liquid ink but has a porous tip that the ink flows through as though it were a marker.

"Molecule" in its modern meaning only dates to 1811. Newton's guess about the nature of light was that it's corpuscular, but "molecule" is a little incongruous.

Green isn't a wavelength, reflection spectrum isn't reasonably described as being a matter of surface texture, and stereognosis (guessing the shape of an object based on touch) is at least as mediated by our sensory receptors and subsequent information processing as vision is.

Pain is not just one sensation. A warning that initial crushing injury could happen if a little more stress is applied feels different than a reminder that you've used a particular muscle enough that recovery is needed, which feels different from a notice that the temperature is almost high enough to cause injury, and so on. Pain, like stereognosis, is more of a conclusion than a sensation. Sound, on the other hand, tells you directly about the resonant frequencies of an object. Big, flexible objects make low-pitched sounds; small, tightly stretched objects make high-pitched sounds.

Orange juice really has pH, acidity, sugar content, and a bunch of volatile chemicals (that we actually smell, but integrate into our experience of its taste). Those don't change when we've inflicted saccharin on ourselves, any more than the shape of an object changes when our skin is too chafed to perceive it readily by touch, or any more than the color of an object changes when we have the after-image of a brighter object interfering with our ability to see it. In every case, we don't notice all the details that our senses are capable of providing. Instead, we have preliminary processing that arrives at a conclusion about what the object is like, and our conscious experience is of something small and pointy, or something orange, or something big and scary-sounding, with categories already imposed on our impressions before they reach conscious awareness.