Leonard Mlodinow —
Randomness and Choice

Fundamental forces of physics somehow determine everything that happens, “from the birth of a child to the birth of a galaxy.” Yet physicist Leonard Mlodinow has an intriguing perspective on the gap between theory and reality — and the fascinating interplay between a life in science and life in the world. As the child of two Holocaust survivors, he asks questions about our capacity to create our lives, while reflecting on extreme human cruelty — and courage.

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is a physicist, and the author of several books including The Drunkard’s Walk: How Randomness Rules Our Lives and Feynman’s Rainbow: A Search for Beauty in Physics and in Life. He's also written for television, including "Star Trek: The Next Generation."

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If you didn't know it, Krista's a Trekkie. And so was one of our guests. A meeting of two Trekkie minds makes for an endearing few moments between interviewer and interviewee. Listen in.

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Leonard Mlodinow at a TEDx event in Bratislava, Slovakia in 2012.

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What a profound and beautiful discussion! Leonard Mlodinow is both clear humane and funny. Your programs are precious and unique to me.....Thank you so much. Lea

Wonderful, thoughtful conversation! Always so rich and nutritious. Thank you!

Some thoughts I had while listening: if we were to reframe the playing field to think of life as a 'game' where we are all extensions of the same life source, choice and free will can come down to one simple thing: you can choose to be your true self or take actions counter to your true self. If you take actions in line with your true self (sometimes this takes great courage), things are less random and more coherent. If you take actions out of line with your true self, life seems more chaotic and random. Of course, this line of thinking passes the can of worms to what does it mean to be your true self :-)

At 33.30 re mindfulness isn't that an assumption that one is reacting rather than acting if all events are determined? If it is who determines right or wrong reactions?

Excellent point -- if everything is predetermined, then we're reacting, not acting.
"Right and wrong" are determined by the society's morality/ethics -- which (as Hume suggested) are expressions of desires -- how that society wants to live. However, determinism has a few discomforts -- for example -- if all actions are predetermined, then punishment and education are useless. To me this seems like a good enough proof by contradiction because it sure seems like punishment can deter undesirable behavior, and education can have a measurable effect on people's lives. I can't prove free will, but I choose to believe in it. If I accept free will as an axiom, then many things make sense in the way that I want to them to make sense (for example: randomized controlled studies about the beneficial effects of early childhood education)

I'm not a scientist at all, but doesn't Quantum physic leave roam for a certain randomness in the universe? In other words, does Quantum physics say you can never completely know the outcome of any event no matter how much you know about the "inputs" if that is the right word? So, if I have that right, could that point to some level of free will?

I'm not a quantum physicist either, but from what I understand, quantum physics is considered to be deterministic because we can predict the probability of an outcome. We don't have to say that a particle will occur in one place 100% of the time. We can say that it occurs in one place 50% of the time and in another place 50% of the time. I think this counts as determinism and doesn't show free will of that particle.

Well yes quantum mechanics only makes predictions about the probabilities of future events. There are several reasons why this almost certainly does not imply anything about free
will as people ususally conceive it. First, the uncertainties associated with quantum mechanics are large for events at the atomic level but usually negligible for macroscopic
entities like human beings. Second, if such quantum uncertainties were at play when people made choices, that would mean that the choices were random (or partly random)
and that is not what people usually mean by free will. Thirdly. though quantum mechanics does not make definitie predictions, some interpretations of quantum mechanics which are
consistent with all experiments hold that the future is predetermined, we just cannot predict it, (These interpretations are sometimes called Bohmian, after the American
physicist David Bohm.) If those interpretation are correct, then even a tiny amount of random (not free) will is not implied by quantum mechanics.

Why aren't spiritual found in the profane? We sure could utilize determined scientific philosophy in asymmetrical economic conditions. We have learned there is a difference between rationality and reasonable conclusions. As much as I respect the Chicago School I think we could learn a thing or two from our saltwater schools.

Would you like to engage in discussion further we'd love your "in-sight" (just playin') in Professor Paul Krugman's New York Times blog titled, The Conscious of a Liberal, which I myself am one. Of course, Krista, you're more than welcome to converse with us - we're discussing this topic (underground of course) and I think he admires your work as many of us do.

Now, my current understanding is with the discovery of the Higgs boson the scientific paradigm has shifted. And, as I'm sure you know, Thomas Kuhn asserted when there's a scientific paradigm shift let the domino effect begin, i.e., all specialization fields of study (e.g. cognitive science and phycology, (social sciences) will shift.

Have you read Thomas Piketty's newest scholarship? I haven't and intend to. Also, I think it's important that the Jesuit you referenced in the beginning of your podcast as been critiques by theologians that specialize in fields of study shared by your self, Leonard Mlodinow. Also, we should remember Negative Theology doesn't necessarily mean Pierre Teilhard de Chardin had no need for God, he just flipped paschal wager. Extremists are a wonderful - not. I would question this assertion interpretation. But, in all seriously, I write with playful and challenging intensions.

In any event, great discussion and will listen more than one time. Great job and thank you both.

Leonard's views are troubling at the very least. Frightening at the most. His theories of randomness not only shatter free will, courage, nobility, etc, but also make excuses for genocide, murder, and every sort of atrocity.

I concur. I went in looking for some brilliant insight and hypothetical reasoning. I love this subject and human misconceptions on this. Instead I found a statements of supposed observational fact which is not useful as he links those conclusions to other views and veers deterministically into a contrived result. Useful discussion from the thought provoking aspect but as far as defining new perspective, I find it lacking in foundational logic that will nurture new and additive wisdom. Ends up where your comment concludes. Not useful. Demeaning to any intrinsic value to the human beings ability to break from lemminghood. This encourages a reduced self evaluation which has drastic influence on society and responsibility. That is not random.

To understand quantum is simple. It is as easy As any thought or action, to understand our relationships is mind boggling
We pretend to know one another but we don't. We only have glimpses of each other . There are of course extraordinary events and moments where the minds of individuals perform the quantum thinking. It is an agreeable . It is love, the only thing that is real.

Thanks for this next installment in the ongoing conversation. Listening, I was able to get clear:
1. Another way to frame the "randomness conversation" is: "We experience events and choices as meaningful. Is that wrong?"
2. I think this is a more fruitful way to formulate the conversation. Yes, it's clearly human-centric, but so is the "randomness conversation" but without admitting it. The "randomness conversation" believes itself to be asking questions about ultimate reality, but really it is talking about reality-as-understood-by-humans. Butterflies and whales would have a very different take on things. Any conversation we have is essentially human-centric.
3. If we accept that, then focusing on the human experience of meaning seems a natural starting place.
4. If we ask, "My father's choice to admit stealing bread has meaning for me. Is this foolish, wrong?" we get a conversation that goes in very different directions from the "randomness conversation."
5. Personally, I think that when we talk about meanings --the human experience-- we find patterns that are far from random. We find that theft and hiding reliably produce complex differences of meaning from giving and honesty. I think these patterns are a significant part of the human condition, and whether these patterns rise out of an underlying stochastic reality or something else is less interesting to me than the presence and shape and power of the patterns of meaning.

Terrific, Krista, thanks. Might be fun to add an expert in logic to your array off physicists. Specifically someone familiar with Kurt Godel's work.I think the gist of his incompleteness theorem is one can not prove the mathematics upon which physics rests and, therefore, prove Leonad's determinism.This from Wikipedia

"Kurt Gödel's achievement in modern logic is singular and monumental - indeed it is more than a monument, it is a landmark which will remain visible far in space and time. ... The subject of logic has certainly completely changed its nature and possibilities with Gödel's achievement." —John von Neumann[9]

In 1931 and while still in Vienna, Gödel published his incompleteness theorems in Über formal unentscheidbare Sätze der "Principia Mathematica" und verwandter Systeme (called in English "On Formally Undecidable Propositions of "Principia Mathematica" and Related Systems"). In that article, he proved for any computable axiomatic system that is powerful enough to describe the arithmetic of the natural numbers (e.g. the Peano axioms or Zermelo–Fraenkel set theory with the axiom of choice), that:

If the system is consistent, it cannot be complete.
The consistency of the axioms cannot be proven within the system.

These theorems ended a half-century of attempts, beginning with the work of Frege and culminating in Principia Mathematica and Hilbert's formalism, to find a set of axioms sufficient for all mathematics.detr

The strange part of physics is the representation that it's OUR inability to explain things that the natural world works by. That's all that "randomness" means, is "we have no explanation". It you just use a little observation... what you see is that change is actually a *construction process* not a "prediction process". The developments of the future arise by BUILDING ON THE PAST. So there's no actual mystery in why events of the past are so uniquely determinative of the future, they are just the unexpected circumstances that the developments of the future develop FROM.

What then works better than the deterministic theory, that nature follows the rules we see in our information (we're the ones that follow those), is figuring our how nature works WITHOUT our information. Where you find the secret is in discovering that the animating force on nature is the building process from which the organization of all of nature's energy using systems develop. The key observation is "they start from scratch, and emerge locally".

Granted, I got that partly from unifying the "wrong laws of physics", finding it was the conservation laws that opened the door, not the power laws. It just works better to explain what we see, and demonstrates its power in a long list of ways, giving us ways for Reading Nature's Signals...

Leonard delivered a wonderfully ethical response to a fairly harsh interview from a person who seems unwilling to accept fact over opinion. There is a difference between the two.

Interesting discussion this morning on free will and meaning this morning, but I'd like to point out one small problem.

Your guest offered not the slightest experimental proof of any of it.

He's a scientist, right? Experiments have to prove hypotheses and so forth? He didn't do this. I suggest, Miss Tippet, that every time a scientist makes a far-out statement, ask him what experiments support his hypothesis. I heard no such experiment mentioned this morning; what I heard was twisted, confusing "logic" and scientific mysticism.

As you did.

And in fact, he is going to turn out to be completely wrong, and it all revolves around one thing. People really do have souls. And it is the existence of these souls that creates meaning and guarantees also the existence of free will. It is only necessary to prove the existence of the soul in the laboratory, and it will fall into place.

Let me be clear. Leonard Mlodinow's assumption souls don't exist is wrong. SCIENTIFICALLY wrong, wrong in the sense the theory the Earth is flat is wrong, wrong in the sense creationism is wrong.

I saw it once---cat-soul dived through my chest---but it is far easier than that.

It is entirely possible to deduce the existence of the soul by the scientific method. Faith is not necessary. As examination of particles in motion yields Newton's Laws of Motion, as examination of charged particles in motion yields Maxwell's Equations, examination of people in motion---human behavior---reveals the assumption of eternal existence. Since human bodies are certainly not eternal, human beings MUST possess an eternal component, i.e. they must have souls.

But you be the judge, Miss Tippet. Since I approach this subject from the standpoint of logic and reason, it therefore must the reader, and the reader only, who must judge for herself whether my arguments are correct and logical---or not.

Miss Tippet, consider the following as a statement of logic, and rank it as "True" or "False":

"If humans possess immortal souls, it should be possible to deduce this by objective analysis of their behavior."


I guarantee you an interesting read.

Oh, and you are going to turn out to be scientifically right in the end, Miss Tippet, and Dr. Mlodinow, I'm afraid, is going to wind up looking rather ridiculous.

(Oh, you like SF? Ok, a little lagniappe. Herewith an SF story about the scientific detection of souls, "AFTER THE AWAKENING"

Nobody knows what effects the scientific detection of souls will have on the human race.

But I do.

www.jeffcorkernsstories.blogspot.com/2008/12/after-awakening.html )

While lisitening to this interview, I noted that Krista Tippett repeatedly suggested that if choices were not free, then they
were meaningless. The guest did not respond explicitly to that misconception. However I contend that choices may
be preordained by the laws of physics and the intitial conditions, but still be very meaningful. They certainly can have
huge consequences and at least in that sense they are very meaningful. In another perspective, the fact that choices
are in some sense preordained by physical law suggests to me that one should not take inordinate pride in
making choices that turn out to be good ones nor be too ashamed of those that seem later to have obviously been

The program did leave me with thought the our lives are predetermined because every action in our lives is determined by a prior action and therefore our thought process at any moment is sum of the prior experiences (parents,siblings, education friends) . My car was in fender-bender .. was that pre-determined because i chose to drive at that intersection at that time....This was before i heard the show.?

If one more physicist tells me I don't have free will I'll slap 'em, or I'll change my mind and won't. That'll show 'em.

Due to the complexity of human beings, each of us is unique; each choice we make is therefore necessarily unique. Uniqueness, by definition, isn't governed by laws other than its own. We call this self-governance “free will”. Of course, this is just ‘scientifically’ speaking.
Although our choices are unique; we say, “uniquely personal”; we all make similar choices. It is these similar choices, based on similar understandings, wants and needs, that make all of us the same. This sameness, this inseparability, this oneness, we call ‘religion’.
Maybe U2 says it better in the song, “One”.

The world has plenty of "others" but only one of you.......the challenge is to be unswayed by those that want you to just like everyone else. I love the work that comes out of this podcast........

I heard that you had an App for the show. When I went to I tunes I discovered there was only an IPhone app. I have a android Samsung S4. Is there an Android app?

Mariah Helgeson's picture

Hi Richard,

There is indeed an Android app. You can download it here: https://play.google.com/store/apps/details?id=com.jacapps.onbeing.

Happy Listening!

In Economic Quantum Wave Theory (EQWT), humans live in a semi-closed ecosphere, where the production of all competing commodities is adaptive, with gradually improving efficiencies but also needing to overcome a gradually increasing entropic impedance to foster replacement. This creates a natural wave for any evolving species but now particularly homo-sapiens, explaining Elizabeth Kolbert's study, The Sixth Extinction. What is pertinent to your discussion with Dr Mlodinow is that the human economic wave is driven by a complex human decision wave, that has both a real and an imaginary aspect. The real aspect is the tangible supply and demand constraints that humans encounter when trying to enact a decision or choice, while the imaginary aspect is a psychic emotive drive to actualize the decision, express an emotion or act impulsively. These two orthogonal dimensions are not always compatible leading to economic overextension, bubbles, euphoria, panics, depressions and bankruptcies. Thus a price is an expected value of energy associated with replacing a unit of a particular commodity. Human preferences take an otherwise random economic energy space and give it direction, purpose and meaning at least according to prevailing human socio-political-economic value structures. In this way, human economics has similar wave particle characteristics to quantum mechanics, where ultimately wave dynamics give direction to otherwise random stochastic trajectories. What is invariant in the economic model as with quantum mechanics is the amount of energy that is available to humanity to create a distinctive economy, and the amount of entropy in a fixed period of time that can collect in our semi-closed ecosphere before a cataclysmic human contraction is induced. Thus we have many choices, but some are much wiser from a sustainable standpoint. This theory is at variance to the Laplacian theory Leonard referenced. EQWT implies that human existence is definitely terminal time-wise, but meaningful in that humanity is elevated or degraded by the sum total of the decisions and choices that individuals make. Some choices will have random outcomes of course, but in total, the signal of human transcendence or depravity is collective. In fact, in ways large and small, every day we are reinforcing or redirecting that signal. Socio-political dysfunctional trends such as genocides, civil wars, sectarianism, racism/classism/sexism and crime are of course part of these signals, but so are the economic trends of consumerism, wealth stratification, pollution, climate change, poverty and corruption which are the sum total of our individual and collective choices. When one looks at individual decision and choices, they appear to have a randomness both in the decision itself and the outcome. But taken collectively, one can take the measure of humanity. Perhaps God is doing just that.

This was a very interesting and provocative podcast, like all that I have heard on this show. Krista, next time you have a scientist on who claims that humans have no free will, please ask him or her how they know that. How do scientists know anything? They will talk about theories and tests by experimental observation, but how can a true experiment be possible without free will? If everything we do is determined (either deterministically as Laplace asserted or randomly as modern theorists assert), how can scientists conduct a true experiment, since their "choices" in setting up an experiment must also be determined? The great physicist John Bell, in commenting on the experimental finding of nonlocal interactions between quantum particles (which Einstein mocked in advance of experimental observation as "spooky interactions"), noted that those findings must either overturn our conception of causality (since no causal relationship could exist between nonlocal particles that interact at distances greater than could be bridged at the speed of light); or the experiments that established that fact must exhibit "superdeterminism". In other words, the outcomes of those experiments must be predetermined just in the way necessary to demonstrate those apparent nonlocal interactions. I think Bell and most reasonable people would regard such capricious determinism as hard to accept.

Another question for physicists: Who is the "observer" in quantum mechanics? How does an "observation" by any being or mechanism subject to the laws of quantum mechanics cause the probabilistic state of a wave function to collapse to a definite state? John von Neumann proved long ago that the state of any macroscopic experimental device observing a quantum phenomenon (like whether a single radioactive atom has decayed in some fixed time) is a superposition of the underlying quantum states. Hence there is no mechanism in quantum mechanics to explain how an observation by a conscious being leads from an indefinite to a definite state of the apparatus. This is called "the measurement problem" by quantum physicists. It's philosophical implications are largely ignored by most modern physicists, though some have pointed to this issue as the physicists "skeleton in the closet". Some very prominent physicists have commented on this issue over the years. Among the most notable was Eugene Wigner, a Nobel laureate for his work on quantum mechanics. A very interesting fairly recent book on this topic is "Quantum Enigma: Physics Encounters Consciousness", by Bruce Rosenblum and Fred Kuttner, two physicists at U.C. Santa Cruz. (). I recommend that you interview one of them for your show sometime.

After reading as much as I can find on these topics, I am fairly convinced that physicists and other scientists don't know what free will or consciousness is, and so they dismiss these concepts as illusions. To me that seems to be an overly dismissive attitude. Just because these concepts don't fit well within current scientific theories is no reason to ignore them or dismiss them. Wigner argued for a new scientific effort to study consciousness and its relationship to quantum physics, without giving primacy to one or the other. Roger Penrose is one physicist who has taken this call seriously, and has a quantum theory of consciousness. He would be another physicist who would be very interesting to interview.

Keep up the great interviews! I love your show!

Hello, Leonard! I appreciate your massive contribution to our understanding of a scientific contribution to the Universe. I am just reading "the War of Worldviews" and choked a little on the forward...Your comment about gastric and peptic ulcers and Helicobacter Pylorii was presented as a successful challenge of the "scientific body" and while it's true what you objectify about the results and Nobel Prize of Warren Marshall, to me this actually serves to substantiate the obstinate scientific mind, in that even though the medical profession KNOWS that the organism H Pylori is the culprit far more often than not, the most prescribed treatments are H2 Antagonist like ranitidine, or a proton pump inhibitors like pantoprazole...any way you look at it , clearly Marshall won the "battle" but the pharmaceutical industry with all its might continually wins the war. This conjecture from a veteran pharmacist. Keep up the good work, back to my cup of tea!

I'm just starting to work my way through this website that I've found so intriguing.The free will debate was very interesting in that it misses an essential point. Namely that the debate is based a belief hidden in our language that we are separate from the universe. That is an illusion, not a fact, and since it is hidden in our language logic will be of no use. As I see it each one of us is the universe becoming aware of itself.

I was struck by the John Wheeler comment of "It from bit" in another podcast. I'm not exactly sure what he meant by that statement,but what I took it to mean is that the universe is a reflection of the yes or no choices we all make. It is true that after the choice is made the laws of physics apply. But I don't think it applies to the choice itself. That choice may be influenced by my subconscious, but that is my choice as well. The subconscious is what I choose to suppress and is not a necessary part of my being. What really got me excited was an extension of my understanding of Wheeler's comment: That the universe is also created by the questions I ask of it and how long I am willing to wait for an answer. This is where we all become physicists, whether we're trained or not.

I'm so grateful for a fellow colleague who turned me on to "On Being." As a high school teacher of an honors philosophy class, it is thrilling to have this program as a supplement to my own growth.

Like many who have commented here, I am not a physicist, and so I dare not enter that arena. However, while it seems that the fundamental laws of physics are definitely intertwined in all action, it does not seem that this can be posited as the only aspect of choice and randomness. A phenomenological account of free will, or how free will presents itself to us in our intentionality, would also be worth a look. Moreover, even scientific method itself is subject to the phenomenological scrutiny of how it is that our consciousness arrives at a scientific appropriation of the world.

What struck me most in this conversation was Mr. Mlodinow's characterization of his father as noble and courageous in his actions, even though they were completely determined. On his account, while we might not have any choice in our actions, we can still use the vocabulary of virtue to characterize actions. Yet, can we legitimately use qualitative terms for people's actions if they are determined? How is it that we can say that the person's actions show him or her to be a "courageous" type of person? On what account? By what criteria? Do we have an innate notion of what courage is, such that we can say that certain actions show the "type" of person that someone is, but then still how can we praise someone for certain activities for which they really have no merit?

Krista mentioned that the deterministic view has been described by some as placing us back in a worldview akin to a tyrannical God. It would also have been interesting to have drawn the parallels with Calvinism and the concept of Predestination.

It seems we are still left with the basic reaction to determinism, which is that whether it is true or not, we are left with the stark experience of painfully undertaking our choices.