This brings us to the link between history and philosophy. You've right that they're not the same thing, but the more I consider it the more I think it distorts philosophical ideas to suppose they can be studied as a single discussion taking place in a kind of timeless present. That notion (for me) is itself one of the ideologically-loaded assumptions of philosophy.On the one hand, I agree. I think it's relevant when studying Plato's thoughts on politics to know that a relatively democratic Athens executed Socrates and lost in a terrible war to the undemocratic Sparta. I think it's important when studying Aristotle to know that when he says plants have souls he doesn't mean by 'soul' what we might think he means. It's worth knowing who and what people are responding to when we read their works, and worth knowing the language they are writing in, both in terms of being careful about translation and in terms of knowing technical terms and so on.
On the other hand, what are you going to do? If we are interested in more, or something other, than intellectual history, then we have to read these works as part of a conversation with us. And we are stuck in the present. I can't make myself a 17th century Frenchman in order to understand Descartes. I can't make myself share his concerns. This limits the extent to which I can understand him and his work, if only in the sense that I will not be able to relate to it as a well educated 17th century Frenchman might. But it doesn't follow than I cannot get anything out of his work.
With (or even without) a little knowledge of the Reformation and the beginnings of modern science I can find concerns either of my own or at least that I can imagine myself having expressed in his work, and take seriously his attempts to deal with them. Understanding Descartes does not mean being Descartes, so I think it's a mistake to think either that we simply cannot understand him because he belongs to another time and place or that we can understand him if only we immerse ourselves sufficiently in that time and place. A field trip to La Flèche will do the trick! No, it won't. But it is worth keeping in mind that he comes from another time and place (though not, I think, another world) partly to keep ourselves alive to the possibility that we might be misunderstanding (especially if he seems to have made a stupid mistake) and partly to increase ourselves (to fend off smallness) by imagining ourselves in very different circumstances (increasing our sense of possibility) and by coming to see how like us temporal and spatial foreigners can be (yes Descartes lived a long time ago, no he wasn't therefore stupid).
It's not so much that Plato thought as he did because of the history of Athens (after all, not every Athenian believed in his ideal republic) but that we might not think as we do about politics if our recent history had been otherwise. I doubt it's healthy to reduce others to mere products of their times, but it probably is healthy to see ourselves more that way, i.e. as products of our times. As long we don't just fatalistically and conservatively accept this as a destiny there is no point trying to overcome. It's also probably healthy to see others as others, not simply as easily 'relatable' versions of ourselves, but I imagine the strangeness is most effectively experienced after the familiarity or by way of finding that relatability breaks down here and there.
Presumably quoting or paraphrasing Wittgenstein, Bouwsma says (September 14th 1950):
That's one way to read Plato: you read and try to make sense, but in the end conclude that he is too foreign for us to judge his work. But Wittgenstein draws this conclusion because he can't find anything good in Plato's philosophy (he likes the myths, but not the arguments). If you can't judge something to be nice don't judge it to be anything at all. If you can find something good in Plato, presumably then, Wittgenstein would have no objection to your judging that Plato is good. Other things being equal, etc.About this time we sat on a bench and he began to talk about reading Plato. Plato's arguments! His pretence of discussion! The Socratic irony! The Socratic method! The arguments were bad, the pretense of discussion too obvious, the Socratic irony distasteful---why can't a man be forthright and say what's on his mind? As for the Socratic method in the dialogues, it simply isn't there. The interlocutors are ninnies, never have any arguments of their own, say "Yes" and "No" as Socrates pleases they should. They are a stupid lot. No one really contends against Socrates. Perhaps Plato is no good, perhaps he's very good. How should I know? But if he is good, he's doing something which is foreign to us. We do not understand. Perhaps if I could read Greek!
Here's more Bouwsma (on Wittgenstein on Descartes):
On Thursday evening we met at Black's. It was my turn to introduce the subject. I introduced: Cogito, ergo sum. After I had finished, W. took it up. "Of course, if _______ now told me such a thing, I should say: Rubbish! But the real question is something different. How did Descartes come to do this?" I asked, did he mean what leads up to it in Descartes' thinking, and the answer was: "No. One must do this for oneself."I'm not sure exactly what this means. Presumably you couldn't ignore the text completely and still claim to know how Descartes came to do this. You need the text to tell you what this is. But you need more than just the text. You need to bring yourself in, your own thinking. Thinking of Descartes as a mere product of his times is a) irrelevant to doing this, b) possibly harmful, in the sense that it would undermine your ability to imagine yourself into his words (where imagining involves not picturing but actual thinking, i.e. meaning the thoughts you think), and c) the kind of bad faith that Sartre associates with Antisemitism and other kinds of racism (because it denies the free will of the person in question). Knowing some history, etc. might help in identifying the this but it won't help otherwise. You're on your own there. And in the present, always.