How does Locke differentiate between knowledge of substance and general ideas? In particular, why does he think that knowledge of nature, like Newtonian physics, is really belief, while mathematics and "morals" (Locke's term for ethics and politics) is where he thinks we can attain knowledge?
Recall that Locke distinguishes between primary and secondary qualities when discussing the objects about which we have ideas. The secondary qualities are not "in" the object, but are sensations produced in the knower by the object acting upon us. This helps explain why it is that you love spicy foods but I can't taste anything spicy without my tongue being set on fire, or why your hear pin drops but the deaf man hears nothing.
<br>Primary qualities, on the other hand, are ...
Locke distinguishes between primary and secondary qualities when discussing the objects about which we have ideas.