Sam makes the claim that science can determine human values. Not merely inform or be useful in constructing. Determine. This is the subtitle of “The Moral Landscape”. The argument is not that science merely can be useful in providing knowledge about reality that must come to bear in making moral decisions, but rather that statements about what state the physical (chemical, biological, neurophysiological) work is in must determine what abstract moral state of affairs we should desire. At least this is what I understand him to be saying.

Sam seems to agree that morality is a domain of what we should do and asks us to consider the fact that all we should be concerned about is a broad consideration of the well being of conscious creatures. Once we admit that there is nothing worse than the worst possible misery for everyone, then morality simply becomes a domain of right and wrong answers away from this global minimum. It is thus "science" (again, considered most broadly as he is fond of saying). Because morality is then reduced to movements across a terrain away from the deepest valley of misery. There may be many different peaks - but the science amounts to an admission that conscious states are brain states in some basic sense. Or, at least, there is some 1-to-1 correlation between brain states and mind states. This may or may not be the case (to consider why not appreciate that identical computer images on a screen may be formed by many different representations in programming code. Here the programming code is somewhat like the state of the mind. The representation might be akin to the conscious state. We just don't know what the relationship between the experience and the mind is. The "hardware" itself in this analogy is akin to the brain: the physical neurons.)

Sam attempts to sideline the age old is/ought debate (that being we "cannot get an ought from an is" as Hume argued. As Bronowski observed we cannot get many of our "is" statements without first endorsing many "oughts" (we "ought" to have a respect for evidence and logical coherence, and so forth). As Sam understands - all we have is “now”. This moment. And that is the realm of science. The study of now. Of what is. Science is of the present tense, even though it may make claims about the past and future. The explanations are of what is, though these can be in terms of what was or what will be (so, for example: it is the case that we observe earthquake tremors and volcanic eruptions and even know with satellites can measure minute changes in the movement of continents...wholesale continental drift that occurred over billions of years in the past and will continue into the future is not something we see now.

But these predictions about the future (or past) are not statements of what should be the case. The predictions of future states that are a crucial part of falsifiable science do not (classically at least) makes any claim about what should be. An astrophysicist explains the evolution of the universe over time - he does not make proclamations about what should be the "ideal" temperature of a star or whatever. And Sam would see no problem with this (I guess) because stars are not conscious and people do not typically have preferences about the temperature of stars (except maybe astronomers studying something very specialised and would dearly like to study, say, a "B" class star). But typically we distinguish between science and morality in the first place, so common sense goes, because there exists in our language, thinking and indeed the physical structure of the universe, a difference between the present and future and so a difference between what is and should be. There is a difference between science and morality ultimately rooted in our fallible knowledge of how the present is, and how opaque the future remains for us.

But although we might grant a premise like "there is nothing worse than the worst possible misery for everyone" this actually cannot tell us what to do next (beyond the absolutely trivial "don't keep doing this"). People will still have preferences and though they may align, Sam's concession that there are "multiple peaks on the moral landscape" means we must account for personal, subjective preferences about what to do next and which peak to climb towards both personally and as a society.

To flesh this out: imagine we are in a metaphorical moral valley together. We see many different ways out and multiple possible peaks and routes to something better. How to choose if all gradients are the same and all peaks of equal height? Like standing at the very base of a bowl where all directions look the same...but there are infinitely many of them. Moreover what if, following David Deutsch in his monumental work "The Beginning of Infinity" that progress is actually unbounded in all domains - most especially morality? In that case the climb ever higher is unending and there can be no "final" ultimate peak to strive towards. Just ever more grand vistas. One may choose to spiral upwards or just take the straightest line. There are infinite possibilities and no "science" of what is can tell us what next step we "should" take if an (almost) infinite number lead upwards away from "the worst possible misery for everyone".  Which way to go to make this unbounded progress in correcting our infinite errors, if there are many many ways to begin the journey? No science can tell us this. Sam’s view is self defeating in precisely this way. More than a simple map of the geography is needed - more than an understanding of the difference between high and low is needed. We need to know how to choose among peaks we wish to climb. And there may be no way to move society or an individual in a "more" correct direction beyond subjective individual preferences. And the very first person "science of subjectivity" that Sam is correct to elsewhere identify as such a crucial part of the rational human conception of understanding our own natures may - when it sharpens itself into view more clearly - reveal exactly this: we simply have preferences that are incommensurable. And this has nothing whatever to do with the fact that physical brains are more or less similar - but rather than the abstract mind that depends on those brains can be vastly different. To misunderstand this is to misunderstand some deep, fundamental physics as it bears on the science of computation (something neuroscientists are - it would seem - terribly ignorant of at this point in our history). All MacBook Air computers might have identical  physical architectures down to precisely the same number of transistors. But this says nothing at all about what they do or even are capable of doing: most of the programs that could possibly run on a MacBook Air computer will never be written and those that have been are as different as first person shooter games and mundane spreadsheets. The brain is like the physical hardware. The mind is the abstract software and just because the former is very similar does not mean that the latter can be made identical. And so for this reason our preferences will forever diverge. We simply do not have the same experiences and so cannot prefer the same things.

To be clear: even if physical brains were very close to identical, this does not mean minds would be. So far as we know, brains are the hardware. But what people do with their brains is very different. They choose different things in life - as it should be. But there is a pervasive misconception out there: brains actually are minds. Brain "states" are mind "states". This is false. A brain state is a physical state. But the mind state is an abstract state and we know almost no details whatsoever about how the latter is represented in the former at anything approaching the level of fidelity that one might think given the way some neuroscientists speak. Neuroscience has taught us some things - but it would seem to be very much in its infancy. Think physics at the time of Newton. There are right and wrong answers...but it's too soon to claim you've solved the problem of how to build a GPS system. But we digress.

People differ in their preferences widely even if their brains are similar. Indeed their preferences can and do change and this is only a good thing. With rational debate I might change my mind about whether I prefer climbing towards peak x to peak y in the moral landscape because someone has convinced me with a philosophical argument even if nothing else in the physical world has changed.

Sam requests we attack the “central thesis of his argument”. Keep in view that this disguises how subtle an undertaking this task proves to be given the way Sam defines science. There is not quite evasion, but perhaps confusion in The Moral Landscape (TML) about what science actually is. So sometimes the "science" of which Sam speaks seems to be that which Popper might be happy to demarcate, but other times Sam quickly slips into using the phrase “rationality more generally” as a synonym when attempting to place morality in “the purview of science”. So we must admit right at the outset that grappling with the challenge to attack his central thesis about the scientific basis for morality as being like challenged to achieve a successful jujitsu arm lock all the while one's opponent, yourself and the mat are covered in oil. The laws of physics might permit such a feat to be accomplished but the slipperiness of one’s opponent place you at a distinct disadvantage given the circumstance he has placed you in.

What slipperiness is Sam guilty of besides leaving open for him to infinitely redefine words like “science”, “rationality” and “morality” when a successful take-down depends upon some constraints upon the meanings of the words? Sam suggests that moral questions can, at least in principle, have scientific answers. His central thesis:

“Conscious minds and their states are natural phenomena, fully constrained by the laws of the universe (whatever these turn out to be in the end). Therefore, questions of morality and values must have right and wrong answers that fall within the purview of science (in principle, if not in practice).” (From his website).

As hinted at above, Sam is careful in TML not to actually ever constrain what he considers to be science as distinct from “rationality more generally”. At times he endorses, and at other times distances himself from, Popper who demarcated science and non-science in terms of what theories could be falsifiable (or testable). Sam admits (as no doubt Popper would) that certain questions are clearly scientific even if they cannot in practice be falsified - Sam’s favorite example being how many birds are currently in flight right now. That question has an answer, but no one knows what it is, or ever shall and the answer just changed anyway. But Sam does not want science to be caught saying that science consists of theories that could only be falsified by evidence - as this just might undermine his thesis. But if science is not that, then what is it? If it is merely “rationality more generally” - who could quarrel with this? Rationality generally includes...moral philosophy.

My own dispute here with Sam, therefore, is that he wants to make the provocative claim that “Science can determine human values” (as the subtitle of TML would have us believe) but then make the far more sanguine move that science is just “rationality” not distinct from philosophy or morality. I agree with Sam that questions of right and wrong or good and evil are indeed matters of fact (true and false) but this does not mean moral questions can be answered by science alone. Science, like mathematics and philosophy, mutually must support one another for us to make sense of the world and create new knowledge.

Sam considers that a proper demolition of his thesis could entail showing that;

“My analogy to a landscape of multiple peaks and valleys is fatally flawed.”

This at least is a strong claim and can be shown to be not only flawed, but false.

A peak implies a maximum. Be it local or global - it is a maximum beyond which no further progress can be achieved. It does not admit of infinite progress. Should we be concerned about this? We should. As David Deutsch explains in “The Beginning of Infinity”, progress in science (and indeed all knowledge creation including moral knowledge) is unbounded. Ever since the enlightenment, great thinkers have proposed that there exist limits to the human capacity to create new knowledge. Famous physicists, philosophers and other thinkers have concluded, based on whim, feeling, personal incredulity and failures of imagination that progress in science will one day halt. Physicist Albert Michelson wrote in 1887 that “The more important fundamental laws and facts of physical science have all been discovered, and these are so firmly established that the possibility of their ever being supplanted in consequence of new discoveries is exceedingly remote.” This right before Einstein published his relativity theories and quantum physics began in earnest. He believed in a limit to progress and understanding.

Today this pessimism about the existence of “peaks” continues; luminaries of the stature of  astrophysicist and science communicator Neil DeGrasse Tyson worry that the capacity of our brains may be insufficient to understand the laws of physics. Sam’s analogy of the moral landscape suffers from precisely the same flaw - if taken seriously. And we are asked to take it seriously. So if we do: then Sam is asserting that there are peaks (summits - maximums - no further progress in morality). But this cannot be so.

It is pessimistic (not realistic) to presume that progress - even in morality - will come to a halt. If the connection is as strong as Sam believes between science and morality (and indeed there is a strong connection between the two, though perhaps as I have suggested not the one Sam thinks there is) then infinite progress in one - namely science - but require (by logical necessity) infinite progress in the other - namely morality. As such, there are no peaks on the landscape. Instead there is simply an infinite sky and we can rise ever higher as our moral explanations improve and our knowledge generally improves.

Related to this is whether it is possible that there is such a state - even in theory - as “the worst possible misery for everyone”. Let us consider why there should be a single state that is the “worst possible misery for everyone”. Perhaps Sam would concede as much. Perhaps there are multiple such states. But perhaps also there are infinitely many. If we can one day (and possibly soon) augment our biological brains with technology to increase our memories and our brain’s computational powers and other faculties besides then the number of “possible states” available to us need not be bounded. The “worst possible misery for everyone” instead is not one point on the landscape, or many - but rather might be more akin to an infinite two dimensional sheet that forms the ground beneath an infinite sky. But - and here is the key - moving upwards in such a metaphorical environment towards greater moral enlightenment as opposed to merely left or right, forward or backwards (maintaining our present state of misery) is not a question for science - but for philosophy. Because if we take analogies like this seriously, we are in an abstract realm of mathematics (or more precisely: logical possibility). Not a physical one. There may indeed be a theoretical one-to-one correspondence between the abstract and the physical (as there is in the mathematics that describes physics) but it is not science that explains that correspondence. It is philosophy.