Spinoza: His views are tricky, because of his particular brand of monism. You’re right that we should generally take the ‘Ethics’ as a work of a priori reasoning, but nevertheless he considered our knowledge of the contents of nature to be empirical knowledge: in order to know that there is a knife on the table, my mind has to interact with the ‘mind’ of the knife, and this involves physical contact.
Plato: The trouble with saying something like this about Plato is that he neither deployed the a priori/a posteriori distinction, nor had views similar to ours about knowledge. And he predates the very idea of deductive logic.
For Plato, knowledge was distinct from ‘correct opinion’ in being unchangeable. This means that knowledge was necessarily not about nature. However, it doesn’t follow from this that the knowledge is a priori. So in dialogues like the Meno or the Phaedo, Plato claims that we have access to knowledge of things like geometry through recollection. If we take him literally, then this could not be in any way a priori knowledge: recollection is firmly an experience (remember, ‘a priori’ doesn’t refer to innate knowledge, or knowledge that is temporally prior to experience). There’s plenty of room to take him less literally, of course.
Ah, but in the case of Spinoza, you can’t get real ‘empirical knowledge’ because to get ‘knowledge’ of the knife on the table, you’d have to learn the entire causal history of the knife on the table. Otherwise, you don’t have knowledge, you have something like an incomplete modification of an idea. So the only way he can have knowledge is a priori reasoning, which is why he relies so heavily on his axiomatic system.
I’ll grant you Plato did not use this distinction, but while recognition allows us to access knowledge, Plato does claim that we already “have it” in some sense. I suppose that makes it debatable whether or not the knowledge is truly a priori: generally we take ourselves to lack knowledge, rather than to have it and not recognize it. Still, if we run with that idea: I might not be remembering some detail at a given moment. My mom’s hair-color, for instance. Nevertheless, we would say that I have knowledge of my mom’s hair before I ‘recollect’ it. Similarly, if we have the knowledge before we have the experience that allows us to recollect the knowledge, that would make the knowledge itself a priori.
As to Spinoza, you make a good point, though using Spinoza’s (or Plato’s) refined sense of what ‘knowledge’ is as opposed to the everyday claims we would today call ‘knowledge’ (e.g. I know that the sky over Chicago is clear today) seems to me to go against the spirit of your initial complaint: neither Plato nor Spinoza thinks you can ‘know everything about the universe a priori’ in our sense of ‘know’. If they do believe that, then it is because they have a much stricter understanding of what knowledge is. It’s not as if they think they can deduce the existence of my pen from a priori axioms.
Point taken, but I would point out that both Plato and Spinoza think that our everyday claims about knowledge don’t map onto reality, so they can’t talk about what we ‘know’ in the everyday sense of ‘know.’ They don’t think that is a valid way to talk about knowledge at all.
I don’t think that’s true. Much of the point of the first Critique was to vindicate experience as a source of knowledge, for which he thought he needed to appeal to certain synthetic a priori propositions (like causality). When we at LW appeal to causality as a necessary part of the map, but not necessarily a part of the territory, we are making a similar move. Kant was the great enemy of metaphysics.
About morality, you’re largely right, though a fair bulk of his writing on morality consists of discussions of social practices and law.
May I add that a failure to ignore these people is a very bad sign for a student: no one (or at least no one significant) has ever claimed this!
Oh, and Plato.
Spinoza: His views are tricky, because of his particular brand of monism. You’re right that we should generally take the ‘Ethics’ as a work of a priori reasoning, but nevertheless he considered our knowledge of the contents of nature to be empirical knowledge: in order to know that there is a knife on the table, my mind has to interact with the ‘mind’ of the knife, and this involves physical contact.
Plato: The trouble with saying something like this about Plato is that he neither deployed the a priori/a posteriori distinction, nor had views similar to ours about knowledge. And he predates the very idea of deductive logic.
For Plato, knowledge was distinct from ‘correct opinion’ in being unchangeable. This means that knowledge was necessarily not about nature. However, it doesn’t follow from this that the knowledge is a priori. So in dialogues like the Meno or the Phaedo, Plato claims that we have access to knowledge of things like geometry through recollection. If we take him literally, then this could not be in any way a priori knowledge: recollection is firmly an experience (remember, ‘a priori’ doesn’t refer to innate knowledge, or knowledge that is temporally prior to experience). There’s plenty of room to take him less literally, of course.
Ah, but in the case of Spinoza, you can’t get real ‘empirical knowledge’ because to get ‘knowledge’ of the knife on the table, you’d have to learn the entire causal history of the knife on the table. Otherwise, you don’t have knowledge, you have something like an incomplete modification of an idea. So the only way he can have knowledge is a priori reasoning, which is why he relies so heavily on his axiomatic system.
I’ll grant you Plato did not use this distinction, but while recognition allows us to access knowledge, Plato does claim that we already “have it” in some sense. I suppose that makes it debatable whether or not the knowledge is truly a priori: generally we take ourselves to lack knowledge, rather than to have it and not recognize it. Still, if we run with that idea: I might not be remembering some detail at a given moment. My mom’s hair-color, for instance. Nevertheless, we would say that I have knowledge of my mom’s hair before I ‘recollect’ it. Similarly, if we have the knowledge before we have the experience that allows us to recollect the knowledge, that would make the knowledge itself a priori.
As to Spinoza, you make a good point, though using Spinoza’s (or Plato’s) refined sense of what ‘knowledge’ is as opposed to the everyday claims we would today call ‘knowledge’ (e.g. I know that the sky over Chicago is clear today) seems to me to go against the spirit of your initial complaint: neither Plato nor Spinoza thinks you can ‘know everything about the universe a priori’ in our sense of ‘know’. If they do believe that, then it is because they have a much stricter understanding of what knowledge is. It’s not as if they think they can deduce the existence of my pen from a priori axioms.
Point taken, but I would point out that both Plato and Spinoza think that our everyday claims about knowledge don’t map onto reality, so they can’t talk about what we ‘know’ in the everyday sense of ‘know.’ They don’t think that is a valid way to talk about knowledge at all.
Spinoza.
Kant claimed one could know most of the interesting things a priori, even if one couldn’t know everything.
I don’t think that’s true. Much of the point of the first Critique was to vindicate experience as a source of knowledge, for which he thought he needed to appeal to certain synthetic a priori propositions (like causality). When we at LW appeal to causality as a necessary part of the map, but not necessarily a part of the territory, we are making a similar move. Kant was the great enemy of metaphysics.
About morality, you’re largely right, though a fair bulk of his writing on morality consists of discussions of social practices and law.
Yes.