Do we have a duty to write concisely and as accessibly, systematically and neatly as possible? It would take a very long time to bring a philosophical essay to the highest feasible level of accessibility -- perhaps a lifetime. Had I subjected myself to this standard in earlier years, I would be long out of the profession by now. And were I to subject myself to this standard henceforth, most of my contributions would arrive years after interest in some issue has faded. Obviously, we have to make a trade-off here. We want to get things published in real time -- presumably also a goal that the taxpayers funding a system of higher education want to see achieved. But we certainly should be willing to accept some reduction in our publication rate for the sake of making these publications more accessible.
How these two desiderata are to be traded off depends a bit on the case. Some philosophical work is read pretty much only by philosophers -- but in some cases this is, you might rightly point out, a consequence of inaccessibility and thus not a good excuse for it. It's really wonderful sometimes to see a gifted writer who can make an esoteric subject matter accessible and even exciting for people outside professional philosophy. But many philosophers, and even excellent philosophers, lack this gift and could achieve wide accessibility only at the cost of producing much less. Isn't it better, then, that they write mainly for philosophers and hope for someone else who will communicate their thoughts in a way that's more accessible to the general public?
So this is then my proposed compromise. As a profession, we do indeed have a duty to communicate our work clearly and accessibly to the general public. We should all be mindful of this duty -- for example by not being dismissive of, or easily dismissing from their jobs, "popularizers" who manage to convey the essence of a philosophical question or debate beyond the confines of the discipline. But not every one of us needs to meet this standard in all her or his writings. Many need not ever meet it if they are reasonably confident that their contributions are or will be clearly reflected in the communications of others. Given the current state of the profession, this compromise would move us some way in your direction. But it would stop short of a world in which every philosophical piece of writing is as clear and accessible to the general public as its writer can possibly make it.
I hope very much, of course, that you will find enough interesting and sufficiently accessible work to keep reading philosophy. Readers like you will keep us motivated to try harder for accessibility.
In a philosophy paper, you are responsible for your conclusions. The quality of your paper depends on how well you can back up what you conclude. In many cases, you can back up a conclusion by citing someone else's work. But in order for that other work to support your conclusions, what it says must itself have some support and credibility. Thus, for example, if you cite a major work of Kant interpretation, which is widely acknowledged by Kant scholars to be very good, in support of your reading of a certain passage in Kant, then this would certainly support your reading. But if you support your reading by stating that your roommate agrees with it, you haven't given much support to it at all. To be sure, your roommate's opinion may be based on sound interpretation. But this basis needs to be added to your cite for it to gain the kind of credibility that the interpretation of the above author on Kant derives from her demonstrated mastery of the whole text.
What matters here, by the way, is not whether that author or your roommate are influential. What matters is whether their views are credible, that is, can be well supported. Your own conclusions can derive support from such views only insofar as you can establish their credibility.
Putting aside whether the rapper is famous or obscure, we need to ask whether his or her lyrics express something that could be backed up. We don't really know how much thought s/he has put into the lyrics and, in any case, even thoughtful people make mistakes or say and sing things they don't really believe. By citing some verses in support of your conclusion, you are putting the text you cite forward as credible. This means you are taking responsibility for the possibility of backing it up. So you should not cite verses in support of your conclusion unless you could explain and defend the content of these verses -- if not in your paper itself, then at least in conversation.
Yes, there are seminal works of philosophy that are of historical and systematic interest for the understanding they convey of what philosophy is. Here I would mention at least a dozen historical works before any more recent academic papers - works by the usual suspects: Plato, Aristotle, Descartes, Hobbes, Locke, Hume Rousseau, Kant, Hegel, Marx, Mill, Frege, and Wittgenstein. With regard to academic papers - by which I take you to mean shorter works published in the last 60 years or so - there is no settled canon. Still, it is pretty clear who have been the leading philosophers of this period; and pretty clear also, in most cases, what their most important essays were. It would be difficult to understand the current state of Anglophone philosophy without having read at least a good smattering of the following: W.V.O. Quine's "Two Dogmas of Empiricism" and "Epistemology Naturalized", Donald Davidson's "On the Very Idea of a Conceptual Scheme", Philippa Foot's "The Problem of Abortion and the Doctrine of Double Effect", Robert Nozick's "Coercion", Derek Parfit's "Personal Identity" and "Equality or Priority", Tom Nagel's "What is it Like to be a Bat?", Bernard Williams' "Moral Luck", Ronald Dworkin's "Taking Rights Seriously", Peter Singer's "Famine, Affluence, and Morality" and a few other seminal works by Elizabeth Anscombe, Ruth Marcus, Saul Kripke, Hilary Putnam, David Lewis, Thomas Kuhns, John Rawls, John McDowell, Jerry Fodor, Patricia Churchland, Dan Dennett, and part-timers Noam Chomsky and Amartya Sen.
I think you are over-reading Oliver Leaman's point. He was contrasting philosophers to historians, pointing out that the latter can rely on a wealth of facts while the former cannot. So I believe he was referring to empirical facts ascertainable by observation, such as facts about bullets and bodies found underground beneath a Civil War battlefield. Such empirical facts constrain disagreement among historians (preventing historians from arguing that the battle was fought with swords and spears, for example). No such empirical facts constrain disagreements among philosophers - or so Leaman may plausibly be taken to have opined.
This claim is less sweeping and fully compatible with your suggestions that there are truths in philosophy. This suggestion seems right to me. Some philosophical arguments are sound, others unsound. Some philosophical positions are coherent, others incoherent. Some philosophical objections are decisive, others fail. It would be quite natural to say that such truths express facts: the fact that philosophical argument X is sound, the fact that philosophical position Y is incoherent, the fact that philosophical objection Z is decisive. But these were just not the kind of facts Leaman had in mind.
Is Leaman right to claim that there are no narrowly empirical facts in philosophy? I find even this more limited claim highly doubtful. It has been disputed in many areas of philosophy. An excellent example is W.V.O. Quine's seminal account of epistemology as continuous with empirical inquiries about mental processes like thought and perception - "epistemology naturalized." Quine's account has been influential also in the philosophy of science. Another example is ordinary language philosophy, which centrally draws on facts about ordinary language. Relatedly, Wittgenstein's later work depicts philosophical problems as arising from problematic uses of language and seeks to resolve such problems by paying close attention to how we actually use crucial words and expressions in our "language games." Further, in moral philosophy there is Rawls's view that principles of justice are formulated on the presupposition of, and in this sense depend upon, certain empirical facts - such as the "circumstances of justice" and various facts about human beings and their dispositions. To be sure, all these views have had their critics. For example, I have been involved in an exciting debate with the late Jerry Cohen who felt obliged to "rescue justice" from Rawls's understanding of it as fact-dependent. So I would not want to claim that there is as yet a settled agreement in any area of philosophy that empirical facts play a fundamental role there (as opposed to a role confined to the mere application of fact-independent philosophical methods and principles). But if empirical facts play such a fundamental role in just one area of philosophy, then Leaman's casual claim is incorrect.
Well, if THE objective in life really is to make money without too much effort, then indeed there isn't much use for philosophical inquiries -- there are better ways of earning money than by being a philosopher.
But is earning a living in the best way really the (one and only) objective in life? I think most people would say that there are other important objectives as well: love, religion, friendship, music, sports, and so on -- but of course people have different views about what matters and how much. So here philosophy comes in, helping us to think clearly and wisely about what matters in life. Perhaps earning an easy living is really the best way to live. But wouldn't you want to think about this, and the alternatives, a bit before you commit yourself to such a life?
Sure, you can become a teacher of philosophy -- most plausibly in a college or university (with a PhD), or perhaps also in a highschool (with a MA). There's not much else, though, for professional philosophers. But then you can also choose another career and keep up with some of what philosophers do as a hobby....
There is a great influence, of course. But it is subtle and impossible to understand simply by reading ancient philosophers. It makes more sense for you to prepare yourself by reading contemporary works that give you a sense of how citizens in the affluent Western countries think about themselves, their relations to the rest of the world, their history, and the world's future. These contemporary works will be more accessible to you, because you understand much better the context in which they were written than you can hope to understand the context in which Plato wrote. And you can still, in a few years, do some study of the ancients if you are so inclined. For now, I would try to find a textbook collection of contemporary essays on ethics or political philosophy, and then learn about the debates we have here about affirmative action, the environment, equality for women, war, poverty, trade, and so on. (By the way, I would give analogous advice to a young Western student departing for a year in China. She should read up on some of the current debates in China and leave the great Chinese classics for later.)
Yes; and I would distinguish two kinds of such aesthetic appreciation. Some philosophers are very good writers, and it is simply wonderful to read them -- some of my favorites are Plato, Hobbes, Nietzsche, Wittgenstein, and Bernard Williams. And in some cases the problem posed or argument presented is stunning in the unity, elegance, or sublimity it attains. I would once more list Plato and Hobbes as examples here, but also some of the less appealing writers such as Kant (e.g., the second analogy of experience) or Rawls (the thought experiment of the original position). This latter kind of aesthetic appreciation is closely related to recognizing a work as philosophically powerful.