Does the World Need a Universal Basic Income? Could Steem Power It?

Technological Unemployment Is Coming

By some reports, 40%-60% of all the jobs in existence today will be gone in a few short decades. Historically, our species has responded fairly well to massive shifts in employment (you’re probably not a farmer, am-I-right?). No one’s crying for the buggy whip makers because Ford didn’t give us a faster horse.

But This Time, It’s Different

For you to understand what I mean, and what this Steem Power is I’m talking about, I’m ending this post here. To read the rest of it, follow along to Steemit and read this blog entry on the blockchain. That’s right, thousands (and someday millions) of computers all around the world, completely decentralized and uncensored, have a copy of this post which the Steemit website is serving up. Not only that, unlike Reddit, Facebook, or Twitter, Steemit pays its content creators and curators directly with value created by the network. When you’re done reading this post, create an account and checkout out my blog and wallet pages on Steem. I’ll post more thoughts on Steem in the future, and I’d love to know what you think.

Determining Determinism

Free will and hard materialistic determinism are polar opposite views on the very nature of our existence as conscious beings. In one camp we have personal responsibility, the importance of good life choices, and the hope that comes with “making” your life better. In the other camp we have a deconstruction of the framework for judgement, shame, and guilt, a recognition of cause and effect influencing every aspect of our lives, and a celebration of the desire to see behind the curtain at the very gears of reality which our brains interpret for action and ideas. What if these concepts aren’t so far apart after all, but instead are simply misunderstood? What if we really do have choices, but only ones that don’t matter?

Let me explain. When I studied computer science engineering at UPENN, one of things we touched on briefly was how neural networks function. To put it simply, imagine a switch which may or may not turn on depending on the input given to it and the current weight setting of the switch. Each switch impacts the input to other connected switches and so on. Neural networks can be trained by a dataset so each switch gets an initial weight setting. Each run through the system after that may adjust that setting for the next run, impacting future decisions made by the network. When dealing with probabilities and dynamic systems striving to obtain optimal performance for survival, it’s valuable to introduce some chance so it won’t get stuck in a loop where every single run looks exactly like the one before it with zero chance for improvement in the future. In this way, a decision gate weighted with a 50% / 50% chance of going either way can break the deadlock and “choose” one randomly to keep the system going.

What if what we call “choice” is more like a 50/50 decision?

I currently lean towards the hard materialistic determinism for a number of reasons. I see too many problems with the current non-materialistic view of reality. As a programmer, my entire professional life is based off of the result of cause and effect. In the world of code, everything happens for a reason. It would be absurd to think my computer would suddenly start acting differently without there being a root cause. The more I study the brain and physical systems in nature, the more I see that same stimulus/response mechanisms at work. Every input we consume from the books we read, the movies/documentaries/TV shows we watch, the online debates we engage in, the podcasts we listen to, the conversations we have, etc…they are all inputs to the neural network system of our brain. One input changes how the next input will be interpreted. If we consider any decision in our lives, we can most likely, with enough thought, come up with a number of previous inputs which impacted that “decision” and how, if those inputs had been different, we would have “chosen” a different path.

So back to the 50/50 choice idea. Sometimes when I’m looking for something to watch on YouTube, I don’t have strong feelings either way. I might narrow it down to a few possibilities, or I might trust Google’s algorithmic choice and go with what’s recommended. If I watch a mindless movie on Netflix, I’ll get the relaxation I’m looking for and enjoy it. If I watch a debate or documentary on the morality of artificial intelligence, it might more dramatically impact my neural network weighting system, further changing my desires and responses to future inputs. Even though the “choice” really didn’t matter to me at the time, the resulting change in my consciousness did matter. It wouldn’t surprise me if, someday, we understand the brain well enough to find a version of the random weighting processor which helps us through those 50/50 “meh?” decisions we don’t seem to care about.

What I find interesting is how those “decisions” end up shaping our lives. How many times has a “random choice” to watch one movie or another deeply impacted your thinking and future movie choices? What about vacationing in one spot over another? What about the people you randomly meet which turn into valuable relationships or future job positions? It’s reasonable to me to see the brain acting as a natural deterministic process which leads to decisions given all the inputs up to that point. When we narrow down our “choices” to essentially equally weighted options on the neural network, our random processor kicks in and bumps one answer to the top which keeps the cycle from gridlock.

That’s my currently theory, anyway. Maybe someday I’ll learn more about this stuff and have a better understanding. Do you have an input to share which might change my view?

For more thoughts on this topic, check out my friend Doug Smith’s blog post De We Have Free Will, or Is Free Will an Illusion? Doug and I had some fun back and forth in the comments you might enjoy.

The Morality of Artificial Intelligence

For a while now, I’ve been really interested in strong and super intelligence along with consciousness itself. My favorite movies explore these concepts such as The Matrix series. I’ve also really enjoyed 2001: A Space Odyssey, Inception, The Thirteenth Floor, Tron, Existenz, The Lawnmower Man, and Dark City. I love fictional books like Avogadro Corp: The Singularity Is Closer Than It Appears, The Daemon, Freedomtm, Influx, Kill Decision, Ready Player One, Snow Crash, and The Diamond Age. (If you look closely you’ll see I’ve listed every book from Daniel Suarez. I love that author’s work. If you have additional books or movies to add to this list, please leave a comment below). As a computer programmer, I’m deeply involved in the tech culture and get to see new things happening a little earlier than most. I built my first websites in 1996 and even then, I was convinced the Internet was going to change the world. I’ve felt the same way about bitcoin, Voluntaryism, and Artificial Intelligence.

Exploring the origins of our morality has been important to me in many ways because of my fascination with the future and how our understanding of morality will shape it. We’re all familiar with the dystopian fictions where the robots take over the world, but how many of us explore the real-world influences which could bring about a hell or a heaven? What things can we do now (if anything) to bring about an optimal future if computers can do everything human brains can but orders of magnitude faster?

Smarter people than I have been talking about this stuff for decades. I’m just happy to be along for the ride. I recently started a Pindex (think Pinterest for people who like educational material) with lectures and content and want to share it with you. It’s called…

The Morality of Artificial Intelligence

The board will stay updated with interesting content like this nugget from Nick Bostrom’s paper: Future Progress in Artificial Intelligence: A Survey of Expert Opinion:


“…the results reveal a view among experts that AI systems will probably (over 50%) reach overall human ability by 2040-50, and very likely (with 90% probability) by 2075. From reaching human ability, it will move on to superintelligence in 2 years (10%) to 30 years (75%) thereafter. The experts say the probability is 31% that this development turns out to be ‘bad’ or ‘extremely bad’ for humanity.”

I hope you’ll join me on the Morality of Artificial Intelligence Pindex board and suggest new content as well. We as a species should work to figure this out. Most experts think a super intelligent future is inevitable and will happen within our lifetime. The question we should be asking ourselves is what morality should super intelligent beings have and why? These aren’t easy questions, and it looks like we have less than 50 years to figure them out.

Where Does Your Morality Come From?

Have you ever considered where your ideas of “good” and “bad” come from?

I think most people don’t give it a second thought. Simple answers quickly come to mind like God, common sense, or mom and dad. Philosophers have discussed ethics for millennia, but sadly most Facebook comments today are completely void of them. All of our ideological battles of individualism vs. collectivism, capitalism vs. socialism, statism vs. anarchy and so forth can be judged by a single metric: Is it good?

Useful philosophy should be as universal as possible. Sadly, we’ve lost our way in even defining good. It’s normal for language to change over time, but some words are so foundational to our motivations and actions, if we change them, we change what it means to live a life worth living.

FallaciesPosterHigherResWhile on this ride, we should also think about what logical fallacies we might encounter along the way, something I hope to do with many of the posts on this blog. If you’re not familiar with, please make it part of your studies. Your search for truth will be greatly improved by knowing these concepts. Thoughts on this post will include No True Scotsman, Appeal to Authority, and Bandwagon.

Now that we’re geared up to avoid logical fallacies, let’s take a look at some common mechanisms I think people use to determine what is “good” and what is not.


I’ll stick with the religion I know best and spent 30+ years of my life in before losing eternity (though other religions could illustrate this point just as well). Most forms of Christianity claim to follow the Bible for just about everything, including morality. The challenge modern, moral Christians face, from my perspective, is how to live true to what they actually believe about morality in contrast to what they are supposed to believe according to the God of scripture. The truly devout (some would say, “fundamentalists”) will argue God can do and say whatever he wants because he created everything and our primitive minds can’t possibly understand him. They come up with (IMO) some rather creative mental gymnastics to justify and do away with the cognitive dissonance caused by exploring morality in the Bible.

From my perspective, the Bible (or the office of the Pope, if you prefer) gives us some pretty conflicting (i.e. not universal) perspectives on things like:

  • Genocide/Violence/War
  • Rape
  • Sexism
  • Bigotry
  • Child Abuse

I could link out to many sources for my concerns above, but they are obvious to those who don’t see the scriptures as divinely inspired, and they are irrelevant for those who do since there’s always another interpretation and justification. You can Google for the same sources I did, but please don’t exclude results from or the Skeptic’s Annotated Bible if you’re truly looking for understanding, not just confirmation bias.

No True Scotsman fallacy shows up with regards to religion if someone replies with “But no real Christian believes that…”


What about using the law for our understanding of morality? On the surface, this might seem like a good idea and be the framework for civilization we all enjoy. Unfortunately, I’m too personally steeped in Voluntaryism to objectively explain how crazy I think this is (I’ve been on the roady to anarchy for a couple years now).

If you desire to be a good person and government law tells you what’s right, how many laws have you actually entirely read? Come to think of it… how many politicians who vote on the laws have actually read them? Yes, in theory, laws can and do change over time to be more adaptive to the consent of the governed, but the track record isn’t so great for things like:

The monopoly on the use of force within a geographic region (how I and others describe government) often uses the cover of “law” to do very immoral things. It’s amazing to me how in the United States in 2016 we actually lock people in a cage for growing a plant. We’re looking for universal philosophical principles here, so don’t even get me started with how screwed up law is in other countries around the world.

To me, some laws can be within the subset of morality, but they are not equivalent. There are laws that attempt to uphold moral ideals (don’t murder, don’t steal, etc), but the idea that morality can come from law is to me a classic Appeal to Authority fallacy as well as circular reasoning.


We might also call this category common sense. So much of our understanding of what is right and wrong comes to us in our early formative years. Those first five years of life are crucial as our brain may be wiring itself to respond to either a hostile, violent environment or a cooperative, peaceful one. Check out for more info on the roots of human violence.

Here are some examples we get from our parents/tribe:

  • Corporal Punishment (i.e. Spanking)
  • Authoritarianism
  • “Because I said so”
  • “Everyone is else is doing it”

This is basically the Bandwagon fallacy. We go along with whatever we see everyone else doing. If our parents thought spanking was a valuable form of discipline, and we “turned out okay” (in our own minds with no comparison set to use for justification), then we’ll probably be okay with spanking our kids (regardless of the studies which argue otherwise).

Now, I have to be fair. Of the categories we’ve looked at so far, this one at least seems the most reasonable to me. We do things which reward us with pleasure and avoid things which cause us pain. As social creatures, our communities provide for much of our pain and pleasure. The part where it loses universality, for me, is when it condones things which can provably be shown to decrease human well-being. But now I’m getting ahead of myself. Why should human well-being matter?

Philosophy and Reason

Now we’re getting to the good stuff! I mentioned human well-being above because I think it might actually be a more universal framework for many of the other systems we’ve already explored.

If there is no God, why did humans independently, all over the world, (subconsciously?) create religions? Why did civilizations all throughout history form governments and create laws for their citizens to follow? Why do moms, dads, and tribes raising children attempt to instill morals?

I think the answer to all of the above could be summarized by it increases (or at least attempts to increase) human well-being. My personal favorite description for why morality based on human well-being matters is because this morality creates the world we want to live in. The philosophically minded readers here will recognize this as a form of Utilitarianism and should be quick to point out the many criticisms of Utilitarianism. That’s completely fine because utopia doesn’t exist in this world. Every few steps forward will involve a step or two back as we further refine and define what it is we’re talking about and, importantly, what we as conscious beings want out of life.

There are literally thousands of years of content to read when it comes to the philosophy of ethics, morality, and virtue. This is the hard stuff. To understand these concepts on a deep level takes many years of study, a journey I’m personally just beginning. Worse yet, understanding the philosophy of morality may disrupt the status quo in terms of our religions, our laws, and our view of our parents’ opinions.

It is worth it! Studying history, I would argue, suggests human progress depends on our pursuit of sound moral philosophy and communicating those ideas to each other.

The wikipedia page on Ethics outlines some key ideas which are worth getting familiar with:

  • Meta-ethics: How we understand, know about, and what we mean when we talk about what is right and what is wrong
  • Normative ethics: The study of ethical action
    • Virtue ethics
    • Hedonism
    • State consequentialism
    • Consequentialism/Teleology
    • Deontology
    • Pragmatic ethics
    • Role ethics
    • Anarchist ethics
    • Postmodern ethics
  • Applied ethics: Attempts to apply ethical theory to real-life situations
    • Bioethics
    • Business ethics
    • Relational ethics
    • Machine ethics
    • Military ethics
    • Political ethics
    • Public sector ethics
    • Publication ethics
  • Moral Psychology: The intersection of ethics and psychology (moral development and the philosophy of mind)
  • Descriptive Ethics: A value-free approach to ethics

Whoa there! That’s a lot to read through! It sure is… not only that, it’s only a subset of philosophy in general. So why bother with all that work? Well, as we’ve explored above, there are problems with other mechanisms for determining what’s good if we don’t have an internalized consistent framework of our own. Religious morality can lead to holy wars and inquisitions. Legal morality can lead to authoritarianism, world wars, and, as the Nuremberg trials showed us, “just following orders” is not a valid defense. Parental and tribal obedience doesn’t create forward moral progress and would still have us all owning slaves or condoning husbands beating their wives (to use just two examples from the last couple hundred years).

Doing the hard work of defining where our morality comes from and seriously questioning those foundations helps create a world for ourselves and our children we want to live in. It’s easy to complain about what’s wrong in society or politics or business but it’s much harder to define exactly what is “good” and what is “bad.” Without doing so, our complaints and the actions that stem from them many not lead to any improvements.

Without a solid foundational moral philosophy, our actions to bring about good might actually promote what is bad.

I’m tempted to end this post here, but I’d like to dive a little further into what personally interests me most right now concerning moral philosophy. I’m a big fan of the non-aggression principle (NAP):

The principle asserts aggression is always an illegitimate encroachment upon another individual’s life, liberty, or property, or attempt to obtain from another via deceit what could not be consensually obtained. For example, the NAP prohibits the initiation of force by one individual or group of individuals against another individual or group of individuals.

The NAP, for me, leads nicely into the concept of Voluntaryism which is a “philosophy which holds that all forms of human association should be voluntary.” I also value self ownership and the philosophy of liberty which comes from it. More on that in this 8 minute video, if you’re interested:

Another, more controversial aspect of morality I’m interested in is where it came from.

What roll does nature play in forming morality?

On a basic, biological level, what is the purpose of life? It is to survive long enough to reproduce the species. For conscious beings, survival involves being in a pleasurable state of consciousness. We have the ability to end our own life… so why don’t we? Because we’re happy. How do we stay happy? Well, that’s a unique thing for many individuals, but it’s easier to talk about the opposite and what makes us not happy. We don’t want to be aggressed against, and we enjoy autonomy to pursue things which increase our well-being. Did natural selection bring about this mechanism which seems to keep conscious species going?

The evolution section of morality on Wikipedia quotes some who argue morality as:

“a suite of interrelated other-regarding behaviors that cultivate and regulate complex interactions within social groups.” This suite of behaviors includes empathy, reciprocity, altruism, cooperation, and a sense of fairness.

There’s even a whole page on the evolution of morality. We can also get into the neuroscience aspects of morality and mirror neurons. The science of morality and ethical naturalism are two other aspects I’m really interested in, along with virtue ethics.

The takeaway here is we should all be exploring what “good” and “bad” mean to us. Before we judge, we should have a solid framework justifying our position. If not, others might easily manipulate us into promoting the very things we’re trying to change.

Where does your morality come from? Leave some comments below to keep the conversation going.

Losing Eternity

From Wikipedia: A comprehensive worldview is the fundamental cognitive orientation of an individual or society encompassing the entirety of the individual or society’s knowledge and point of view.

Not something we can easily change, right?

Whether we like to or not, we know each other by the labels we use. Both those we project and those we store as mental representations of others. The combination of all of these labels forms our worldview. These labels influence how we think which then changes how we form new labels and interpret existing ones. We make associations between labels, words, and actions. Surrounding the whole mix are emotions which lack words of their own.

Let me give you an example:

I, Luke Stokes, no longer think the label “Christian” applies to me.

How does that feel? For some, a smile and a chuckle, welcoming another adult out of the world of make-believe. To others, a tragedy of deception from demonic forces with eternal consequences and ultimately damnation. I know people in both of those extreme camps. The largest labels cause the most division. Our religion, our political party, our sex, our physical appearance, our position on controversial moral issues… these can all cause pain and separation. They form neat little boxes our brain quickly references without having to evaluate each person as an ever-changing individual.

Over the last couple of years, I’ve changed. For a little background, I grew up in a Christian family, served in Christian ministry for 6 years (which required me to raise financial support from others), and worked for a company with a Christian mission statement for almost 4 years after that. Decades of my life are aligned with the label “Christian” from my music, to my friendships, to my presence on Sunday mornings. For many, it would be hard to think of me without thinking about that label (and their various versions of what it means). My hope is for people to see me for who I am and talk to me about ideas as I see them today, not as a set of labels would dictate.

I’ve hesitated to talk about my story mainly because I’ve been trying hard to figure it out first. I haven’t blogged in over a year and a half. I know what it feels like to remove a label you’ve assigned to someone, especially if important aspects of who they are to you come from that label. These labels often shape our understanding of moral character, trustworthiness, and empathy. Changing them brings a feeling of loss, like a member of the tribe has moved on. The “us” vs. “them” mentality can take over, increasing division and alienation. Conflict arises as questions are raised which other worldviews have already settled and don’t want to revisit. Rehashing tough questions is seen as a waste of time and energy or, worse, a threat to the status quo. I now think those around me are even more confused to think of me under one label while hearing me say things which fit others.

So here I am with a new blog and a new approach to understanding myself and my place in the world. My current fascinations include voluntaryism (basically the principles Jesus preached about, minus the divinity/supernatural), epistemology, philosophy, neuroscience, morality, reason, logic, and more. I want to make sense of the life I’m living. I want to live on purpose. I want to learn about how my brain works and how it doesn’t. I don’t want to live in shame or fear concerning things which may have nothing to do with morality or human well-being.

In short, I want to pursue truth [1][2], no matter where it leads.

The problem with this approach, I’m now realizing, is the more I learn, the more I recognize how much I don’t know and how wrong I’ve been in the past. It’s a humbling and somewhat censoring process (hence no blog posts for the last year and a half). Let me give some examples.

Growing up, my “Christian” homeschool curriculum (I use air quotes there, because I don’t think the books actually accepted Jesus into their heart as Lord and savior) explained how evolution isn’t real. I now think it is real [3][4] and those who claim otherwise have some confirmation bias going on, from my perspective. And yes, abiogenesis is something different from natural selection, please don’t confuse the two. I was taught to believe false things about the nature of reality and some of it was done in very fallacious ways. That really bothers me.

Let’s go with another even more controversial example: abortion. My parents are no longer with us, but if they were, I’d probably be having some amazing conversations with my mom on this topic. We used to have the best discussions. As a child, I can remember her peacefully protesting for the right to life for what she (and most pro-life advocates) consider to be defenseless humans being murdered. I now take a more nuanced approach. If life starts at conception, why don’t we value single cell or simple multicellular life equally in all species with the potential for high levels of consciousness? Have we rationally and philosophically come to our perspectives or were they handed to us by centuries of dogma? Other than our level of consciousness, is a human being fundamentally different than an animal if we both got here through evolution? When it comes to abortion, why do we also ignore the clear evidence of (at a certain point in time) two fully-functioning conscious human beings occupying the same space? It’s somewhat arbitrary to only call it two lives once the birth takes place and the separation is more clearly defined. So we’re left with a complex question we don’t yet have answers to: When does a clump of cells become a conscious human being with its own claims to life and liberty? Why does a clump of cells have more say about human well-being than a fully-functioning human woman whose life (and maybe whose family’s life) would be forever changed (often negatively) if these cells fully develop into an unwanted child?

How about another one: corporal punishment. Is it ever okay to inflict pain on children as a form of punishment? Every church I’ve ever attended says it is. My own understanding of morality and reason say otherwise (along with many who have spent decades studying this stuff [5]).

Are human beings fundamentally evil by nature? Is authority good for humanity or does it bring about our own corruption? Can non-violent communication and the concept of violence being a tragic expression of unmet needs bring about long-term change in the world?

I could go on, but we’ll leave these questions and others like it for future posts. The intention of my old blog was to encourage others [6] and though I still intend to do that here, this blog will probably be more inward focused. A way to explore my own thinking while challenging the thinking of others and creating meaningful conversations.

So where has my search for truth led me so far? Well, let me lead with some questions I’ve been pondering over the last year or two:

  • How much of my belief system was originally determined by the country I was born in? How much of it by the beliefs of my parents?
  • Do I believe thoughts, memories, emotions, feelings, etc—things we can provably demonstrate originate as functions of the physical brain—can and will exist in an afterlife without a physical body as we know it? If so, why? What evidence do I have for that belief beyond my own emotions?
  • What are my thoughts on the God of the Gaps? [7]
  • How much of my belief system is based on an unquestioning view of the Bible without having actively pursued textual criticisms of it?
  • Do I believe a square circle can exist somewhere in the universe? (no) Do I believe consciousness without matter can exist somewhere in the universe (or outside of the universe for that matter), and if I do believe it, why do I believe it? If matter is involved (such as a miraculous Jesus), what of the “super being” argument instead of a deity?
  • What evidence or reason for believing do I have that humans contain a spirit, and do all evolved beings also have a spirit or were we the lucky primates and if so, why?
  • Given the large amount of things I previously thought I was sure about concerning Christian dogma, history, human perception, etc, how can I reliably trust the things I know now without adopting a more skeptical, rigorous, scientific epistemology?
  • What level of evidence should I require to believe things which have no known, provable representation in the physical world?
  • How do I explain the accepted theories of human evolution and the idea that we mastered fire which enabled us to pre-digest our food which led to more neurons which led to the brains and consciousness we now enjoy? [8]
  • How many skeptical views about my beliefs have I deliberately studied and considered?
  • Given the many contradictory (and changing) views on such fundamental religious concepts as the afterlife, how can I put so much assurance in it? Some argue hell is a second death, not eternal at all. Others say the concept of hell was invented later in the religion. And what of heaven? Is it on earth or not? Who are the people outside of the walls?

In short, I’ve lost my belief in eternity as taught to me in the Bible. As I started working through these questions, I listened to even more audio books, lectures, debates… always reading and learning. Looking at the world through other peoples’ worldviews teaches your brain something and fundamentally changes how it responds to new information in the future. Learning about the brain via books like Thinking, Fast and Slow [9] and Predictably Irrational [10] have fundamentally changed my understanding of what it means to experience existence.

The questions above should not be taken as a direct challenge to anyone else. They are part of my own personal journey.

In summary, my mechanisms for separating out opinion from justified belief have changed, and I think the long-term result is beneficial for myself and my family. Pursuing truth means leaving things which appear to be less-than-true behind. It means following the path, no matter where it takes you or what the personal cost might be. I’ve already lost very meaningful connections by being honest about my thoughts on these issues. Thankfully, I’ve also started some great dialogues with true friends who may not agree with me but love me just the same.

I don’t know where this road will lead me and for once in my life, I have great peace about that. I’m no longer pretending to know things I don’t know. For the things I’m passionate about, I’m now way more open to criticism, correction, and alternative perspectives (but you’ll certainly get a strong argument out of me). I’ve embraced love as a truly powerful force which can change the world. I want to be part of that change, and I think it starts by being honest with myself and those around me while removing faulty thinking and dogma. I’m still quite off in many ways because I understand computers more than people, but I am always improving.

Regardless of how my labels change over time and the emotions that may cause for those around me, I will do my best to be true to myself and continue growing. I hope you can accept me for the individual I’ll be tomorrow.

[1] – Religion for the non Religious
[2] – How Religion Got in the Way
[3] Stated Clearly
[4] It’s Okay to Be Smart – 12 Days of Evolution
[5] Upworthy – The science of spanking: What happens to spanked kids when they grow up? (infographic)
[6] Bestoked at (my old blog) – Blogging Is the Mental Projection of Your Digital Self
[7] – What is so special about the human brain?
[8] Wikipedia – God of the Gaps
[9] Wikipedia – Thinking, Fast and Slow by Daniel Kahneman
[10] Wikipedia – Predictably Irrational by Dan Ariely