Agnosticism IS the most dishonest position

[Belacqua]

When we imagine, we are selectively rearranging things we've previously perceived into a new combination that does not exist in reality.  Even if I were to imagine something that exists, like a Pear, the product of that process is not an abstraction but the mental equivalent of a concrete.  I'm unable to imagine an abstract pear.  I've got to give my imaginary pear specific measurements.  It has a specific size, shape, color.  If there's no measurement ommission, then there's no abstraction.  If there's no abstraction then there's no definition.  Instead there is a description.  My imaginary pear is 6 inches long, has yellowish green skin with a red blush on one side. It tastes sweet and slightly tart and it has a grainy texture.  I am unable to imagine a Pear with no specific color, weight, size, etc.

I suspect there may be intermediate stages in what we imagine. The pear you describe is imagined in detail, but that doesn't mean that everybody always does it that way. 

For example, if you ask someone to draw a cat, some people can draw one very accurately from memory, meaning they have "in storage" a detailed picture of a cat. More often people will draw something stylized and cartoonish -- sort of a symbol of a cat. (And the ability to draw something, I'm sure, doesn't depend on manual skill but on the clarity with which one sees it.) If we say to someone "imagine a cat," I'm not sure that they will specify in their mental image whether the cat is male or female, calico or gray, etc. 

I can't speak about your own mental images -- maybe everything you picture is complete in every detail. But I'm skeptical that people generally work this way. 

Here's how you can tell if something is imaginary vs. real.  When you think of an imaginary thing being different, then it's different.  Now it is red or purple because I imagined that it changed color.  But when I think of something real changing to something else, it remains exactly what it is.  

Doesn't this just indicate that your imagination is limited? Like I think that Obama is a real person. If I use my imagination, I can picture him getting fat or going bald. But that doesn't mean that he's not real. Of course in real life real Obama hasn't changed due to my imagination -- but we're talking about mental pictures, here, right? I didn't say anything about imagination influencing reality.

This is exactly what happens with a god.  If I imagine it as an old man then God is an old man.  If I imagine it as a cloud of energy, then it's a cloud of energy.  If I imagine it being omniscient, then it's omniscient. That's because if I want to apprehend God, then I have no alternative but to use my imagination.  One can can ascribe any quality or characteristic to something that is imaginary including the quality that some things about it are unknowable. And this is why there are thousands upon thousands and even millions of "definitions" of God.

Well, if you imagine God as an old man, then you have a mental picture of God as an old man. It's a mental picture. This leaves all the hard work still to do: is your mental picture at all related to reality? If God is really an old man, then we should be able to show that without reference to people's fantasies. 

Yes, there are lots of definitions of God (pace what Rahn127 was saying). And all of them may be pure fantasy, or one of them may be in line with reality, or some of them may be partially true, or any number of other combinations. 

Imagining something is necessary but not sufficient if we're talking about the real world. First you imagine a hypothesis, then you use logic and empirical evidence to check your imagined thing against the world. 

The fact that people have imagined different things doesn't change whether one of those things is right or not.