Ah sweet Reason, you merciless yet loyal mistress.

In my youth, Reason was the first Big Thing I discovered.  It took me years and years to get a handle on the concept and the myriad implications that followed.  A set of concentric circles of indirect discovery and subtle yet solid truths, it all starts out with a basic idea, usually called the principle of non-contradiction:

Contradictory statements cannot both be true in the same sense at the same time.

To put it more simply, contradiction is falsehood.  Anything that inescapably leads to contradiction is falsehood.

If we claim a box contains only a single apple, we can’t simultaneously claim that it contains also a nectarine.  Those two claims contradict each other, they can’t be both true in the same sense at the same time.

It may seem foolish, but this approach, along with a handful of what I sometimes call “primaries” – starting beliefs or assumptions – can get you quite far.  So far, in fact, to yield the best (the most likely accurate) approach to understanding the cosmos.  Yes, that short idea brings into fruition all of science and math.

Here’s one quick, rough illustration of how someone can leverage such a simple thing into useful, practical results.

Many (if not most) religions are exclusive.  That is, the claims they make are not compatible as written with each other.  For example, the old Norse religion – with Asgard, Odin, Thor, Loki, etc – is very fundamentally different in its “truths” than the old Greek religion – starring Olympus, Zeus, Poseidon, Hermes, etc.  There are similarities, of course, but compare the truths of one with the truths of the other and they simply don’t match up, unless you turn a blind eye, which we will not.

The fact is, the Norse religion could be true.  It’s possible that upon dying you may wake up in Valhalla.  Alternatively, the Greek religion might be the true one – perhaps you might find yourself on the slopes of Mount Olympus after death.  Or it could be some other religion – Christianity, Islam, Judaism, the list goes on and on.  Any of them might be the true one.  Of course, another option might be that none of them are accurate.  It may be that upon death, you die, and you don’t ever wake up anywhere else.

The thing is, while we can talk about the science of the mind, what if anything happens supernaturally after death is not a subject anyone can prove or disprove.  The Greek and Norse religions are as valid now as they were when everyone believed them – and will continue being so.

So that means it’s OK for people to believe whatever they want about what happens after death, since they can’t be proven wrong – after all they might just turn out to be right, yes?

Actually, if you apply Reason, you will see that such a choice is not rational.  This is why:

Whatever the justification someone uses to believe that the Norse religion is really true, it’s the same justification the person following the Greek religion is using.  And yet this justification yields two very different religions that contradict each other.

Therefore the tool that produced such contradictory “truths” is itself invalid, and simply must not be used as justification.

In fact, only the kinds of justifications that do NOT produce contradictory facts are useable, are valid.

And there we have it.  Starting from the abstract principle of non-contradiction, we end up at a practical yardstick for what is a permissible justification for our beliefs and what isn’t.

Of course, that’s just one simple admittedly off-the-cuff example of how to get pragmatic results from Reason.  There are countless more examples: all of science and math result from Reason applied to our observations of the universe.

I will go one step further, and state what most rational people think or feel:

Reason is the ONLY appropriate tool for understanding the objective truths of the universe, for discovering facts and knowledge relating to anything that we can claim exists.  If Reason cannot deliver a truth to us, it is better not to pretend to know such a “truth”.  Or to put another way, sometimes the only rational answer to a question is “We don’t (yet) know.”

Reason alone – and all that is generated by it (like math and science) – is the sole and only arbiter of factual truth.  If asked “Does X exist, is X real?”, Reason is the only valid way to find the answer – and the answer will either be yes, no, or “we don’t know (yet)”.

So when a religion says “the earth sits on the back of a giant turtle” and claims that idea is factually true, the religion has overstepped its bounds onto Reason’s court.  There are still vast spaces for religion and spirituality to expand into: explorations of value, metaphor, purpose, intent, personal evolution, and so on.

But when it comes to factual and objective truth, it has to be justified using the tools of Reason.  It has to be proved.  The only reason to accept any statement as true, ultimately, is because to not do so would be demonstrably irrational – that is, lead to a contradiction.

Now it’s perfectly fine for religions to have metaphors, creation stories of the world to teach and inspire us.  Just so long as no one tries to claim that these stories are factually true.  Even when they claim something small – for example, the existence of a city in the ancient past located at such-and-such a place.  If no proof of this place is found, then it is a story, not a demonstrable fact.  And if proof of this city is found – say archaeological remains – then the proof isn’t the religious writings, it’s the result of the science of archaeology, a branch of science, the daughter of Reason.  We can only come to factual truth through Reason or its descendants.

This is the core life philosophy I have been on a journey discovering and developing for the last few decades – that to know truth you must know Reason – and that if you ignore or subjugate Reason, you no longer have truth.

I thought that was it, that no more was needed.  After all, if Reason is the sole avenue to all truth about the world, about what is and isn’t, about basically everything in the cosmos, than why would anyone need anything more, right?

Actually, no. As it turns out, Reason is sufficient to give us factual truth, objective truth – but understanding this world and how it works is not enough.  It is not enough to answer the question how – we still have the need to understand why.

And we also need to do more than understand stuff.  We need to connect.  We need to find our place.  We need to figure out how we should live our lives and why.  Sometimes we need stillness to look within, other times we need the support of a close community.

We need to pursue regular transcendent and meaningful experiences that resonate with depth and profundity.

Life isn’t just about understanding the facts of the world, the science, math, and history.  That’s just the beginning of living life – knowing what’s what.  But after embracing Reason and the truths that flow from it, many new questions follow, questions that Reason cannot answer on its own:

What’s next?  Why bother?  How can I feel most alive?  How do I get what I need?

What do I need?

This is the domain of Spirituality, I think.  This is where you go when Reason’s work is done – or at least well underway.

So go there, if you like, and see where that leads: Spirituality.