system
Given the following post, respond as if you're commenting on Reddit:
human
Given the insanely large number of philosophical views which have been defended in a serious way, and foundational disagreement, how does one avoid begging the question against some?

I'll briefly explain what I mean by giving examples. It seems like many subjects discussed in philosophy are very complex and even for foundational questions there have been some serious philosophers who offered a defense of all sorts of different takes. What I see a lot (also here!) is something like this:

Q: So, why can't we say that we treat this paradox like so, and thereby we defuse the contradiction?

A: Hey hey hey, some people argue that there are true contradictions and that the paradox is actually a sound argument. Maybe you don't want to beg the question against them and tell us why we need to resolve the paradox?

Q: It seems like that theory in the philosophy of mathematics just doesn't match the facts about mathematical practice and can't explain ...

A: Stop, who says that it's mathematical practice that judges the philosophical theory? You're presupposing a second philosophy but many people have argued for a first philosophy which grounds mathematics! You're begging the question against the proponent of a first philosophy, why would they care about your complaint?!

In either case A cited disagreement about more foundational things (like are contradictions REALLY bad or what even is the right relation between math and philosophy) to counter more specific proposals. But it seems that makes it almost impossible to get off the ground. How does one say anything in philosophy without begging the question against some views?
gpt
You don't. 

You don't have the time or space or brainpower to respond to everything, so you construct arguments aimed at people who share some common assumptions. 

You might worry that this means that we can never be truly justified. So it goes in life: all the rest of our knowledge works in largely the same way. There are possibilities out there that we haven't fully considered, and there's no good way to argue against some of them without making presuppositions that won't be universally accepted. So you get by on what seems to be safe at a given context (in this context, second philosophy, because grounding mathematics in philosophy is *cray*) and do what you can with it.