What is taken as truth in philosophy?

Question

First and foremost I should say that I am not educated in Philosophy; I study Mathematics.

Essentially, the job of a mathematician is to prove theorems by logical deduction from axioms, which are statements considered to be true in advance. The axioms themselves are essentially up to the mathematician, in that so long as they don't contradict each other any statements could be treated as axioms for some system. In the experimental sciences, similarly, what is taken as absolute truth is observation: what nature is seen to do.

My question is this: in philosophical arguments, what is taken to be true? Is there an equivalent to what I've described above?

Answer 1

Philosophy is not different from Mathematics or other disciplines which need a starting point or basis from which to begin. Virtually all of the arguments in philosophy rely on an agreed upon starting point, such as the use of a particular logical system for which to judge the validity of arguments on either side. Not every philosopher proposes a complete framework for rational discourse; they often assume you already understand the formal logic system they use, for example. Others take a more long-winded approach and synthesize existing systems into a comprehensive framework for reason and knowledge (e.g. Kant). But on a foundational level most philosophers hold a few axioms to be true.

In Western philosophy, these principles or axioms are referred to as the Laws of Thought:

Law of Identity

"That every thing is the same with itself and different from another." A is A and not ~A

Law of Non-contradiction

"One cannot say of something that it is and that it is not in the same respect and at the same time." In other words, it states that contradictory statements cannot both be true in the same sense at the same time, e.g. the two propositions "A is B" and "A is not B" are mutually exclusive.

The Law of Excluded Middle

It states that for any proposition, either that proposition is true, or its negation is true.

_{(paraphrased from various Wikipedia articles)}

Answer 2

In philosophical arguments, the premises are typically claims that either (a) other philosophers have already argued for, and so are recognizable from the literature, and typically cited to some sources, or (b) the arguer thinks can be made plausible on their own, either prima facie (at first glance) or by appealing to some briefer, further motivating argument.

In the context of arguments, then, premises are generally not taken to be truths per se, but rather plausible starting-points. They may be thought to be true, but they may also be taken to be merely plausible, or agreeable to the intended audience of the argument.

I note that in the experimental sciences data is not generally taken to be absolutely true. Typically, statistics assumes error. But that's of course apiece with agreeing that data offers a starting point for argument in empirical disciplines.

Answer 3

Certain parts of philosophy are looking for well founded axioms, from whence further claims can be derived. For example, Discourse Ethics and Argumentation Ethics look at what is necessary for argumentation, and exclude arguments that are so called performative contradictions.

For example, the argument "Conflicts should be resolved by force." is a performative self-contradiction. Why? Because, if he who claims it really believes that force should be used, he would simply do that, instead of engaging in argumentation, which is the non-violent form of conflict resolution.

For similar reasons, arguments that deny self ownership (as an ethical norm) do not make sense. For, to contribute something to a conversation, the contributor must surely be in control of it's own body, or else he could not speak, write or do whatever is needed to convey his ideas. Furthermore, by engaging in argumentation, he who denies self-ownership must have previously asserted self-owenership and the non-violence/non-agression priniciple, i.e. he must have asserted that ethical norms can be found and agreed upon - at least in principle - through a rational discourse.