How I Know What I Know, Part I: Worldviews

A while back, a friend of mine suggested that I look into the idea of a "worldview".  I've since done so, and have seen the term used with increasing frequency in religious discussions.  Put broadly, a worldview is the set of all things that a person accepts as true; it acts as a lens through which new information is filtered.  The concept, originally put forward as Weltanschauung, is central to German philosophy; however, it has become fairly popular with the religious, as it allows them to put forward their religion as something other than a set of testable hypotheses.  I've found this growing trend to be particularly troublesome for a couple of reasons.

First, there's a tendency for people to consider their worldview to somehow be sacred, and this is not so.  Yes, I get the point; you're not arguing for the claims of your religion, you're arguing from them, because you simply assume them to be true.  But this does not mean your worldview is not subject to being questioned; it just lets me tell you that you're making really stupid assumptions.  The trouble, of course, is that someone who has decided to classify their beliefs as a worldview, and also decided that this puts their beliefs somehow above being questioned, will not be swayed by facts or reasoning.  Many people who use the "worldview defense" in this way are simply closing their minds to dispute; they have decided that they are right by fiat, and nothing can prove them wrong.  It is a fancy way of admitting to willful ignorance, and I think it's ridiculous.  This puts me on the side of the philosophical realists.  Just because someone makes certain assumptions about the way the world works, that doesn't mean that their assumptions cannot be questioned, because they could be incorrect assumptions.

Which leads me into my second point.  The other way in which the "worldview defense" is used is to point out that I, too, have a worldview that is based on assumptions.  Since everyone is assuming something, the claim is made that all such assumptions are equally valid, and thus the religious assumption that god exists is something I can't argue against.  After all, there are things that I believe that I can't prove or disprove, so that makes their beliefs just as good as mine.  Hogwash.  I readily admit that I make certain assumptions about the way the world works, but mine are very limited.  Just because some assumptions are necessary, and just because everyone makes assumptions to build their worldview, that doesn't mean that we can just assume whatever we want.  The assumptions being defended by religious people when they make this claim of "well, it's my worldview" are not reasonable assumptions to make.

So, what assumptions are reasonable?  This is the meat of this post; I am going to begin to describe my own personal philosophy, as I have been giving it significant thought as of late, and that must rest on the foundation that one might consider my worldview.  What do I assume to be true about the world, and do the assumptions I make invalidate any of the arguments I make against religion?  Let's dive into that.

My way of looking at the world is very strongly based in evidence.  However, I must admit that there are things that cannot be shown to be true with evidence, hence the necessity of assumptions.  But the question of what assumptions I need to make is a very important one.  I think that we can successfully justify everything with only three assumptions, which is a pretty strong ratio of assumptions to explanations. To begin with, one must discard all beliefs; start from a blank slate, and try to reconstruct the knowledge that I had before.  And since we have nothing on which to build, we have to start with assumptions.  I think, however, that these are things that are universal; everyone assumes that these things are true, because if they didn't, they couldn't function as a human being.  The first two assumptions are necessary to have any knowledge at all; not using them ends any epistemological discussion before it begins.

• Contemplating the existence of my mind justifies my belief in the existence of my mind; "I think, therefore I am."
• At least some of my sensory perceptions are accurate.

Arguing against these assumptions is difficult; do you not think that you exist? Do you never trust a single bit of sensory input? Such radical skepticism is pretty worthless, and I don't think anyone who really followed it would even be capable of engaging in a discussion anyway.  The first assumption is fairly weak, but unavoidable.  Simply stating "I think, therefore I am" assumes that there is an "I" to think.  The second assumption is much stronger, in part because it is not a blanket assumption.  I am not assuming that my senses are always accurate; indeed, I'm well aware that my senses can be fooled.  I've misheard things, seen things that weren't really there, confused one physical sensation for another, etc.  But overall, my senses report a consistent external reality, and assuming that they do sometimes report this reality accurately has not led to any irreconcilable contradictions over the past 20+ years of my use of that assumption.  It is strictly not something that I can prove (how would I do so without appealing to sensory input?), but it is a strong assumption because if it were wrong, I would be very likely to have experienced something that seriously shook my faith in it.  A third assumption is needed to describe how we gain knowledge:

• Physical evidence is a valid means of justifying beliefs.

This assumption builds on the second, and thus works with it to form a strong foundation for the rest of my belief system, or worldview.  Again, I think everyone makes use of this assumption.  I believe, for instance, that I am typing on a keyboard.  My senses are providing me with physical evidence that the keyboard exists, and that physical evidence justifies my belief.  While this could, in theory, be argued against, I don't know of anyone who will honestly do so; how could they?  Do they not believe in things for which they have physical evidence, such as the existence of a pen sitting on their desk?  These three assumptions are the only ones that I make, or at least I ideally try to make only these assumptions.  The assumptions themselves are, I think, rather uncontroversial; it is the claim that they are the only assumptions necessary where many people, not all of them religious but most of them, disagree with me.  From this simple foundation, I think we can make an evidence-based argument for anything, including the thesis that evidence is the only valid means of justifying beliefs.  This is the central thesis of evidentialist foundationalism.  I highly recommend the following two videos for a remarkably lucid explanation of evidentialism, and a response to some common criticisms of it.  They are from a user on YouTube known as Evid3nc3; his entire series on his deconversion from Christianity is of incredibly high quality.

I'm going to stop here for now, but I intend to go a bit further in a following post.  There are numerous other positions that I hold, numerous other things that I believe in.  But they all stem from this basis.  This is a worldview that does make sense, that makes only reasonable assumptions.  It is open to comment and criticism, and because the number of assumptions being made are so very few, it has the beautiful characteristic of admitting that I could be wrong about almost anything.  You can, of course, disagree with me; my worldview is no more sacred than any other.  I just happen to think that I can defend it on its own merits, rather than using its worldview status as a defense.