Memories are fashioned. Their built in much the same way we build with Lego or bake a cake. Once built a memory is rarely ever static – it changes as we retell it or bring it back to consciousness. So a memory is constantly being rebuilt. This is not a problem really except with how we normally conceive of memories. We rely on memories to hold together our identities – to keep all the important facts straight about who we are (or more precisely were). We also depend on memories to help us make sense of what happens in the present – it gives a context to fit our experiences. Most of all trust our memories to tell the truth – since most of us are reluctant to admit that we would consciously lie to ourselves we faithfully use our memories as evidence about what is real and what most certainly is not.
Memories are slippery. Surely you've witnessed the story told by a friend more than once. Each telling is a little different than the first telling. Char often 'gets' to hear me tell the same story over and over again. Although it is hardly a conscious thing – each telling of the story is adapted slightly. The recollection is altered to accommodate speed of telling, eliminate uninteresting details, include details pertinent to the context of each telling of the story, and so on. It's hardly the same story every time. But surely just because something is retold especially in ever so slight variations, does not mean that what actually happened changes. Certain not. But what actually happened – in all its specific glory – is rarely very relevant. We are only actually interested in those parts of the memory that are useful in some way. Recalling who pulled the trigger in a murder scene is useful in determining where guilt should lie. But there are actually thousands of details about that same scene that we care nothing about and could not even recount. So our attention is drawn then to those details that seem to be most useful. But if its true that memories are slippery then how are we to know that even those details that we or others find most relevant are reliable. We don't know. Consider magicians for a moment. Their craft is built on helping us to focus on details that prevent us from seeing how the 'trick' is being preformed. This is not because we are lazy but because our brain is designed in such a way are to focus on those things which it can reason as most important. We simply cannot process the multitude of extraneous information available to our sense at any given moment. But this is hardly the most slippery part of memory. If memory was not slippery cross-examination would be pointless at a trial. Our memories can change in the telling so that in the telling we are not merely recounting some fact as if it were an absolute number but we are actually believing what we are remembering. What we believe in then is not what actually happened since it is no longer available to us completely an since we have actually changed it – even if ever so slightly.
We are not typically bothered by this slippery nature of memory. We can tolerate minor changes in the story as long as the main points remain the same. We also are hardly ever interested in listening to or telling the whole complete story. And of course we hold certain rememberances in higher esteem than others. If it is written down it is usually more trusted as the authentic expression of what took place. A statement to police or a biography are relied on as more important sources. But written documents have a crucial flaw. They not only write into permanence those things that are consider to have happened but also just as concretely write out those things which are deemed not to have happened (whether due to insignificance or otherwise). Some of the most controversial sections of the Bible are precisely those that do not say or can (no longer) say important information about where when and how certain events happened (Take the great flood for instance). The permanence of the record becomes highly problematic when building a definitive natural history for example. So a text's strength immediately becomes its weakness.
What it all boils down to is this: memories are not nearly as useful in determining the actual content of the past as they are in telling us about the people who hold the memories and tell them. And this is very useful information indeed. Far more useful than what we commonly refer to as 'the facts'. Facts are hardly irrelevant. They are just not nearly as useful for constructing faith, belief and trust as they are commonly seen to be. Knowing what is left unsaid and unremembered is easily as useful for that. Convictions are better served by carefully extracting out from behind the 'facts' the ideas that have motivated the fashioning of these 'facts'. But this means that we approach memories with an intrinsically counter-intuitive perspective. I suggest that doubt – that fine art of intelligent (and not simply dismissive) questioning – ought to walk side by side with belief. The two should haunt each other always.