Sam Harris has argued on many occasions - the earliest of which I'm aware of being in his book, The End of Faith, as well as later on in The Moral Landscape - that it is (at least theoretically) possible for us to scientifically determine what is good and what is evil. He argues that the only assumption we need to make for science to be able to make this determination is that it's bad for there to be a universe which results in the worst possible outcome for all sentient beings. Upon that foundation, he argues, we can theoretically build an entire scientific discipline of determining what should be done to maximize good (ie. that which is the opposite of the bad defined above) in the universe.

Is this logic flawed in any way? Clearly, this science would be extremely difficult to realize in practice (having to take every ramification in the universe of every action into account?!) - but is it theoretically sound?

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    Empirical science has nothing to do in moral issues, that's the field of the Philosophy, wich is purely theoretical. There no way to determine if an act is "bad" or "good" by an experiment. What's the worst scenario? It's depends on the philosophical position on what's the good, i.e. quite different between utilitarism, existencialism and estoicism. – Apocatastasis Jun 14 '11 at 0:40
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    To define a Bad universe, worst possible outcome must be determined first. What scientific factors can deduce how worse a situation is for a given sentient being ? would the same factors be applicable on next sentient being ? – user2411 Nov 5 '12 at 18:30
  • Even philosophy can't determine "badness"/"goodness". It can only give many possible choices and ideas. – zaarcis Mar 5 '13 at 23:56
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    Is-Ought problem notwithstanding, we can in practice simply agree on a foundational principle and build rational moral systems ("scientifically determine good and evil") from there. I think the foundational principle is as he states, or more generally, that existence is better than non-existence. We can't really justify this, and that's fine, because as long as we agree we can determine which lifestyle choices amongst us (religious vs non-religious in this case) are more or less likely to uphold this principle. Not all beliefs require logical ("scientific", as Harris terms it) justification. – stoicfury Mar 7 '13 at 6:05
  • btw, is it really philosophy of science (as tagged)? i think it's exactly opposite – Bulat Jun 24 '13 at 17:21

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There is no way to take a non-moral "is" and from that extract a moral "ought". (ref) This separation is usually called "Hume's Law". This has been not only a pretty self-evident, but also generally accepted law within philosophy, but nevertheless it regularly pops up wanna-be philosophers trying to break it and failing.

As science can only concern itself with what is, it can not talk about what ought it is impossible to scientifically determine any moral issue, including god and bad and evil.


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    @Ruben: 1. Moral realism and moral anti-realism is a false dichotomy. But surprisingly 41% thought aesthetic value was objective too, so clearly 41% of academic philosophers are complete morons. Which sounds about right. And 39% leans towards platonism in favor on nominalism as well. I hope at least these groups of idiots are mostly overlapping. 5. I'm right for the right reasons. If you are right for the wrong reasons, that's good, as compared to being wrong for any reason. – Lennart Regebro Jun 20 '11 at 15:54
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    I'll look forward to somebody objectively proving the aesthetic value of objects. Until then I retain the right to claim that academic philosophers who say beauty is objective despite having studied the issue and hence been told why this would be impossible and makes absolutely no sense, are idiots. Sorry if this offends you. – Lennart Regebro Jun 24 '11 at 2:07
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    @philosodad: The argument is not "because Hume said so". The argument is Hume's law. Whom the law has been named for is completely irrelevant. I even make a short and IMO succinct summary of the argumentation. In fact, I only mention Hume because I say that the law is usually called "Hume's law". How you can get that to be an appeal to authority is beyond logical comprehension. – Lennart Regebro Jul 10 '12 at 19:58
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    -1. Regardless of Hume's Law, the fact that "is != ought" doesn't imply anything about out ability to discern what "ought", under some set of guiding premises. Science doesn't tell us what is, but rather proposes models which describe uniformities in what is. The proposed programme is to identify "how we ought to act" with "what will achieve the best outcome": not to identify what is actually the case about X with what ought to be the case about X, but rather what would actually promote well being with what we should try to achieve (without a common proposition X being modified). – Niel de Beaudrap Oct 31 '12 at 1:43
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    @NieldeBeaudrap: The problem there is that you assume that promoting well being is good. Which you can't scientifically prove. QED. Also, rephrasing "what is" as "what uniformities there are" doesn't change anything. That's just a rewording. Science still can not determine what ought or what we should try to achieve. – Lennart Regebro Oct 31 '12 at 5:59

If  you take it as a given that "it's bad for there to be a universe which results in the worst possible outcome for all sentient beings" and presumably similarly that what is "good" is what results in the best possible outcome for all sentient beings, and if  you assume that you live in a universe obeying classical laws of physics (or you're willing to settle for quantum probabilities), and if  you have a computer with approximately the same amount of RAM as there are particles in the universe, then you would still  have the problem of dealing with a multi-valued objective function.

In calculating the "worst possible outcome for all sentient beings", do you weigh all sentient beings equally? Do you employ a hard cut-off in determining sentience? (E.g., how would a chimpanzee fit into all of this?)

So, no, it is not scientifically possible to determine good and evil, although given certain (philosophically inspired) assumptions  about what makes an action good and evil, it would be fair to say that science might allow us better guesses as to what actions are "good" and "evil".

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    It's worth pointing out that the reason that Harris uses the phrase "Moral Landscape" is because he is postulating the existence of a landscape in the sense of a solution space: I.E., we can't know, even in theory, if we are at THE universal maximum, but we can make observations about the local conditions and work from there. – philosodad Mar 5 '13 at 23:35

Harris is either

  1. engaging in a bit of circular reasoning when he uses what is effectively a synonym for good ("well-being") to define good, or
  2. he is essentially grounding morality in what amounts to hedonism (which Dawkins more or less admits when he says that Harris bases his entire proposal on the removal of suffering).

(1) doesn't solve anything because it slips common notions of the good in through the back door. (2) opens up a Pandora's box of problems and consequences, some of which undermine Harris's other positions (e.g. biology doesn't prevent organisms, including humans, to evolve which experience pleasure/pain differently; if all activity, including science, becomes motivated only by pleasure, then why should the truth necessarily matter?; the questionable formulation of the common good and its raison d'être; and so on).

I wouldn't spend too much time on Harris's work. He's poorly versed in philosophy, and consequently philosophers don't take him very seriously (if I recall correctly, even Dennett once expressed serious reservations about Harris's competence in this area).

  • I don't think that you can make the statement that Dawkins admits something about Harris' argument. The argument does not belong to Dawkins, and he is not in a position to make admissions about it. Also, defining a term with a phrase or synonym is not circular reasoning. – philosodad Mar 5 '13 at 23:38

As far as Good and bad are seen as relativistic terms, science can help to know whether the outcome of a cause will be good or bad, however the final judgement has to be done on by the intellects of man. A good is good because it helps to advance towards a predetermined goal. The means to achieve that goal has to be vetted on moral grounds, and I feel science doesn't have such faculties to vet the path taken and there is exactly where the difference emerge For example, lets say population growth of a country is increasing at a very high level, and it is required to reduce it. Science can't see why it should be wrong to end life of some to achieve this, as long as it is an option to serve the purpose, though morally it is wrong.

  • So, if there are two contradicting goals, any action leading towards goal A will equally be against the goal B. What is the action in this case, a good or evil? – bytebuster Nov 11 '12 at 5:51
  • If you make a system that works on a set standard, it can check whether the action is inclined towards A or B and tell accordingly whether it is good or evil. Just that, but it can't tell why it is good or why it is bad except that because it has been told so. There science fails and only intellects like human possess can help with that, that weighs the task on a moral ground and involves emotions with it. – sarath Nov 15 '12 at 16:06

Science is wholly unable to tell us what should be. It can only tell us what is. If you imagine someone seeing a Lion tackling a Gazelle. Now we can in accordance with the scientific method perceive that the lion has killed the Gazelle. We can posit reasons as to why he does so. Maybe he is hungry. Maybe he is driven to survive and propagate.

Now can we use the scientific method to determine if the Lions SHOULD eat the Gazelle? No we cannot. Can we use the scientific method to determine if the Lion is being fair to the Gazelle? No we cannot. Science simply cannot answer these questions.

Now that does not make them not worthy of consideration. Neither does that mean we should a hold a view of agnosticism towards these questions. It simply means the scientific method cannot answer such a question.

It is to me a young budding scientist alarming to see such a claim. Atheism has no right to be spokes people for science as a whole. Neither does it have the right equate scientific enterprise with atheism.

You should remember that Sam Harris is only speaking for Sam Harris. His views are not the views of the scientific community as a whole. Their are many scientist on both sides of the religious divide which would disagree with him.

  • "Science is wholly unable to tell us what should be." The position that Harris is taking is that this is simply not true. It isn't that he's unaware that this argument has been made, he disagrees with that premise. Also, in his definitions as put forward by the OP, morals don't apply to Lion behavior. – philosodad Mar 5 '13 at 23:41
  • Maybe my examples where a bit simplistic but I think my point is still valid. – Neil Meyer Mar 12 '13 at 10:27
  • You miss my point. The fact that morals don't apply to Lion behavior is secondary, the main point is that Harris simply does not agree with your premise. He is aware of your premise and has an argument for why your premise is wrong. You have not presented a valid argument or example which supports your premise, so from my perspective there is no reason to believe your point to be valid. – philosodad Mar 13 '13 at 1:14

Not surprisingly, most people here asserted that moral propositions are not under the scope of science. Perhaps it is one of the arguments to support the philosophical independence .

Generally, I agree with what most of the people here said, but I need to expound it further. Empirical inquiry does not solely refer to natural sciences if we are talking about moral philosophy. When we say Empirical or scientific inquiry, we simply refer to a meta-ethical justification stating that physical feelings can correspond to a certain moral value. Thus, hedonism and utilitarianism are forms of empirical justifications, because it equates goodness with pleasures. In a first glimpse, we cannot see any absurdity in that. After all if we are all satisfied, everything is good.

But ethical non-naturalism challenges this ethical justification. Ethical non-naturalism argues that combining pleasures and satisfactions cannot constitute to anything aside from being pleasurable. As such, the term "good" is not a physical property, rather it is an irreducible component of a particular action. Thus, an action should satisfy a certain objective standard to deductively justify the intrinsic goodness of an action. This means that the term good is not empirical and is not synonymous to pleasures, because we will still ask what made pleasures good or right?I am not saying that hedonism is wrong. I am just saying sciences can use hedonism to make morality entirely empirical. But it failed because goodness is not an empirical property.

There are also other attempts to make morality scientific, one of which is through psychology. It argues that external influences shape our moral convictions. According to these people, mind sciences give a better view about morality. However, these sciences only discuss the "motivation to act", and not cannot justify an action. Suppose that a person killed a rabbit, mind scientists would assert that a person did that because there are some uncontrollable impulses that forced that person. But this does not account for any moral value. Is it immoral or moral? Therefore, mind sciences only compliments moral philosophy after it has justified the value of an action. it is sound to say that John became immoral, because his peers are likewise, because we have defined immorality. But it is absurd to say that John is influenced by his peers to kill, thus killing is immoral.


Science can tell you an awful lot about contingent oughts ("in order to achieve X you ought to do Y"), and it's not completely clear that non-contingent oughts even exist. (We like to think they do since it saves arguing about whether X is worth achieving, which ends up with the realization that we don't have a satisfyingly solid grounding for knowledge, etc..)

Unfortunately, Sam Harris doesn't really delve into the issue adequately; rather than making a spirited defense of the value of contingent oughts like e.g. Daniel Dennett does, he just expresses his feeling that of course science can tell you what you ought to do. (And not in a very impressive way, either--he starts with really clear cases where everyone agrees what to do and notes that adding a scientific perspective doesn't change anything, and then as far as I can tell dismisses the rest as details.)

Instead, it would have been nice if he had brought to bear the full force of contingency, including extinction if you screw up too badly. Harris' personal views seem to be very typically American--highly individualistic and happiness-based, in particular--which may explain in part why he didn't go in that direction. Happiness is great and all, and it's nice not to worry about people telling you what to do. But when one starts from "we're intelligent social primates in an indifferent and largely deadly universe", it's hard to get to a point where you don't start thinking it could potentially be a good idea to curtail individual freedoms to maintain environmental sanity, and that we should probably demand a much higher degree of attention to nurturing our offspring to enable them to make informed decisions about this complicated technological society we've built.

(Someone needs to write a book titled "Your Feelings are Trying to Make You Evolutionarily Fit in a Social Context".)

Anyway, I view the is/ought divide as probably much ado about nothing; I think when we end up fully exploring the force of contingent oughts, we may have enough. (In a way similar to coherentist views of knowledge--you can't perfectly ground things, but when everything you care about ties together, that's good enough.)


Yes, but that would require inclusion of concepts from Informations Theory, AI, Physics and coming up with some notion of Weighted Emotional Entropy and myriad of other conceptual structures that is by far beyound human comprehension, but when our superior robot overlords take over they will muse over how their human pets do a crude form of Philosophy and squable over definitions of good and evil instead of doing a simple (to them)compuation.The notion of Computational Philosophy Theory is maybe far beyound the reach of humans that can keep at most 7 things in their head but to a machine roaming over giga-tera flops of computational power will be just plain obvious.

Humans can be very well represenred as complex neural networks, and what ever that humans can perceive can also be modeled. Turing test will be turned around, those who pass it will be considered machines and those who don't will be the cute human pets.

To say that human morals can not be broken down to pure calculation is only short sighted arrogance on humans part.

PS: Instead of scientifically, good and evil can be computaionally calculated.

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    I had a physics professor who used to say the simplest model of the universe that captures all of its behavior is the universe. That might be a slight oversimplification, but I think it's basically correct. Furthermore, there are sometimes good reasons why our complex neural networks make snap judgments instead of weighing all possibilities—sometimes if you take the computational time required to calculate an optimal solution, you've passed the time when that solution would apply. – Ben Hocking Jun 14 '11 at 1:47
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    @Ben, That is because the neural netwroks have been trained for some specific tasks, that is how we have survived as species this long. Yes it is a given that for human to try to calculate the optimal solution it might not feasible, but it doesn't mean that for higher beings it is also true. – jimjim Jun 14 '11 at 2:37
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    there are calculations that just can't be performed in even an infinite time on a Turing machine with infinite memory. I mean sure, if you want to posit entities that exist outside of logic, then anything is possible, but for entities operating within the realm of logic, there are real problems that can't be solved exactly, but for which guesses sometimes suffice (such as the Halting Problem). – Ben Hocking Jun 14 '11 at 10:48

Yes, it is possible to scientifically determine what is good and what is evil if you allow definitions of good and evil.

Let us take an example: Is it evil to torture and maim babies for entertainment?

If you believe that this question is simply a matter of opinion, you have a purely local definition of good and evil that amounts to good being stuff you approve of and evil being stuff you don't.

If you do not believe that this question is a matter of opinion, than you must be taking the position that there is something about that action that puts it into the class of things that are "evil", as opposed to things that are good. Harris takes the position that "good" and "evil" relate to suffering and happiness, and that since the suffering and happiness of conscious beings are observable facts, we can use science to promote the latter and reduce the former. This is true, we can in fact use science to reduce suffering and increase happiness.

Harris defines this as "moral", which is where other people disagree with him. So what is interesting to me is that in terms of goals and facts, many people agree with Sam Harris, but they reject that you can define evil, and therefore reject the argument itself.


easy. good and bad are social scores, like nice and pain are biological ones. so everything that's advantegeous for this concrete society, considered good by its ethics. of course, societies are different (like species), so for example in Communism goal to become reach considered as bad, while in Capitalism it's good

but many, if not most things are good for any society. these are like biological instincts, i.e. things required for every animal to keep alive and get lot of children. in the same way, any society need that you will be ready to kill its enemies, work, create family, produce children, keep its religion/ideology, don't violate this particular society laws (written and non-written) and so on, so on

  • Please check out how to write good answers if you want to avoid spending a lot of time with answers that get downvoted. – iphigenie Jun 24 '13 at 12:55
  • i still don't see why it should be a bad answer, except that i don't follow existing phylosophies. it's easy to check that ethics is strictly defined by society needs like the pleasure and pain are defined by biological needs. probably everyone will be happy if i can make reference to famous old Philosoph, but i can't. although my view may be considered as developement of Marx philosophy who have said "social being determines consciousness".... Nevertheless, if someone need to SCIETIFICALLY determine what's good and bad - i propose the solid MATERIALISTIC theory. like no other? – Bulat Jun 24 '13 at 16:59
  • Then I will simply say that you are wrong. – iphigenie Jun 24 '13 at 17:07
  • thak you for the good answer. ok, i will add that it's impossible to answer a complex question is a short manner. obviously, people perform things that are bad for their own societies - just in the same way that auto sometimes don't ride. but ethics was created by society to force men to disregard their biological needs when they contradict to society needs. i suggest you to start studying from the common cases rather than search for contradictory ones, which you can find to any real-world theory. just for example - what cases of murder are moral? – Bulat Jun 24 '13 at 17:18
  • btw, are you agree at least that good/bad are SOCIAL MOTIVATION engines, like pleasure/pain are BIOLOGICAL ones? are you know a en.wikipedia.org/wiki/Pleasure_principle_(psychology) ? – Bulat Jun 24 '13 at 17:24

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