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A Basic Mistake In Philosophy
November 13, 2008, 9:04 pm
Filed under: Epistemology

A whole host of problems in philosophy trace back to a very basic mistake.  

It works like this:  All we directly perceive is our own internal ideas/sense-impressions/sense-data.  We never directly perceive things like trees, tables and friends.  Instead, all we perceive is our internal mental ideas or representations.

If we are philosophical rigorous, so it goes, we must admit that we can at best only infer things like trees, tables and friends from our internal ideas.

But there are major problems with these kinds of inferences.  I won’t go into the details, but the long and short of it is that it doesn’t work out very well.


But is it true that all we directly perceive is our internal ideas?  I can’t think of any good reasons to think so.  Our internal ideas/sense-experiences/sense-data aren’t what we perceive at all.  Instead, we attend from them to other things.  We don’t perceive them, but perceive by means of them.  Consult your own internal sense-experiences.  Notice that you don’t perceive them, properly speaking, but by means of them you perceive something else.  

I don’t sense a sensory experience and then infer that there’s a tree in backyard.  Instead, I simply see that there’s a tree in my backyard by means of sensory experiences.  

I directly perceive the tree in my backyard.  That is, I don’t perceive the tree by perceiving something else.  I perceive the tree by means of a sensory experience, which is itself not perceived.  Of course I can, as a kind of second order act, consider my sensory experience focally.  In this extended sense I can say that I perceive my sensory experience, but only this this unusual extended sense of ‘perceive’.  The important thing to notice is that this is completely different from perceiving a tree.  


You are probably thinking: if I directly perceive things like trees, what of hallucinations?  Aren’t these proof that I don’t directly perceive trees but directly perceive something like sense-data?  Aren’t hallucinations merely mistaken inferences from sense data?


Our sense experiences are produced by our cognitive faculties.  Perceiving a tree is a matter of our cognitive faculties (the ones aimed at the production of true belief) functioning properly and furnishing us with true belief.  It might be that we’ve been drugged, and so our cognitive faculties aren’t functioning properly.  If so, then our cognitive faculties might misfire, producing false sensory experiences.  But notice that, even here, we don’t perceive sensory experiences, but perceive hallucinations by means of them.  In any case, we have no reason to think that, just because of the problem of hallucinations, we never perceive anything but our internal ideas.


4 Comments so far
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What about revelation, Ed? How does that tie in with what you’re thinking in this article?

Comment by Christopher

I agree with Alvin Plantinga’s account of the sensus divinitatus. When we are put in the right kind of situations or circumstances, this cognitive faculty kicks in, producing in us true beliefs about God. God designed us that way. Of course, since the Fall, the sensus divinitatus has become an idol factory. We trade the truth for lies, because that’s what we fancy, and so God has given us over. That’s why we need to be encountered by God savingly in order to come to know him rightly. We need to be rescued from our own idolatry and self-righteousness. This happens through the preaching of the Word in the power of the Spirit.

Comment by the.pilgrim

I thought I was fairly intelligent until I read this post. I have not the vaguest concept of what it is that you are trying to say here. It seems like it must be something interesting, but I really don’t know because I can’t comprehend it.

Comment by craig

While reading your post it occured to me that although we don’t consiously perceive our senses when the focus of attention is a tree, isn’t it possible that the senses are being perceived sub-consiously? And if so, would that change your argument?

Comment by Chris J

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