Does philosophy have rules or methods for reasoning or analysis like, say, the "scientific method" in science. If yes are there any differences and what are they?
So let's suppose that there's no "scientific method", it's not something I'm particularly convinced by, but it seems to be the gist of the discussion. One way to look at your question, then, is not in terms of method per se, but result. How do science and philosophy overlap in terms of their contribution to human society or knowledge?
In those terms, I reckon you could say that philosophy is an immature but not redundant science. It grew out of philosophy, as natural philosophy, and then was developed by e.g. Francis Bacon's ideas about a "scientific method".
Empirical science historically developed out of philosophy or, more specifically, natural philosophy.
I don't know if a definitive answer is possible to this question, but I would say the most commonly shared method for philosophy is argumentation.
Within this, the most commonly agreed to foundation is Aristotle's three laws of thought. And then past that sentential logic whether formalized or not is broadly accepted within philosophy. For the purposes of answering, I'm going to call this "logic."
Are there exceptions? i.e., philosophers who don't use this type of logic. I'd say there's three kinds of exceptions:
- technical exceptions -- people who are still trying to do logic but reject some minor feature of the canonical forms and explore the possibilities of these alternatives.
- "postmodern exceptions" -- people who are attacking the canonicity and codification of reason. But this is still done (in general) against the backdrop of the historical philosophical project(s).
- "breakdown exceptions" - this might be a variation on (1) or (2) but Davidson and Rorty spring to mind as thinkers who think that when you get to the end of logic, you find that it does not work.
But even so logical argumentation is the core of both what the canon and the detractors do. (with "logical" taking on different meanings for the detractors).
Outside of this, I'd say there's a great deal of difference in terms of how philosophers do philosophy, varying from highly empirical methods to highly idealistic methods, from atheistic to theological to indifferent, from moralizing to nihilistic...
You might consider philosophy as the study of all methods of reasoning. Every major philosopher has his or her own original method, which forms part of the core of what makes that philosophy distinctive.
Science is the development and exploitation of one particular method of reasoning, which originated within philosophy, but proved to be uniquely valuable even to the world outside philosophy.
As virimaior discussed, logic is the foundation of many diverse philosophical methodologies, but it is perhaps best understood as a common (but not universal) tool of a wide variety of philosophers.
Whether or not there is such a thing as a "Philosophical Method" is in itself highly dependent on what definition of "philosophy" one espouses and different people have held widely different definitions throughout history.
For an overview of this, the Wikipedia article is actually decent enough: https://en.wikipedia.org/wiki/Philosophical_methodology
I want to hasten to add that while a lot of commenters are speaking out against there being a scientific method, scientists do generally agree more on what science is and is supposed to do than philosophers do on philosophy. So as dynamic and alive science as an endeavor may be, the notion that science does not generally share at least a few common features is just as much a fiction as the idea that every scientific discovery is based on a specific method. Philosophy on the other hand can genuinely be considered inhomogeneous in goal, methods, topics and everything else, really.
So to sum up, no there is no accepted Philosophical Method but there are accepted Philosophical methods within certain sub-fields or schools of philosophy.
I would follow up on the lessons of the history of science and say 'absolutely not'.
Science itself already does not fit into the methodologies that it sets up for itself (q.v. Kuhn).
It impossible for those to be expanded or tuned to allow all reasonable science to fit within them. (q.v. Feyerabend)
Philosophy is a wrapper that includes the whole of science.
Therefore, philosophy cannot possibly fit into a methodology.
Another way of looking at the overlap would be to ask what makes philosophy good philosophy, or science good science.
I think most should agree that good philosophy is rigorous, and that this is something it shares with science. So if you look at the difference with pre and post Socratic philosophy there is I think a tangible improvement in its soundness (think of the above mentioned laws of thought and their certainty), just as science has increasingly explained away its anomalies.
Obviously that rigour isn't quite the same: in philosophy there is so much disagreement, less is settled, that it becomes much more polemical and less progressive. i.e. the philosophical community is more divided, across the board, and this reflects in how it approaches the idea of proof, which is, if not less stringent, then more contested.
You can compare this with something like literature, or painting. Would you say that the arts become more rigorous, or just more interested in questioning their assumptions (as in e.g. early conceptual art)? The arts are less about the theory underpinning them, than their realisation in a work of art, and this reflects in being, I think, less conclusive.
Agree with the comments above concerning such a thing as "Scientific reasoning." There is such a thing as the Age of Reason (circa the late 19th Century) where many of us Westerners thought we had conquered ideas such as War, famine, etc through the use of "Reason" (use of evidence to advance an argument or create a greater bounty for all of humanity as two examples.) Philosophy is never to be bound by what I think they would term "such externalities." Logic is even worse sadly.
Of course what is a "reasonable amount of money" is always an interesting point of inquiry....