The Is/Ought Problem of Morality – Can Hume’s Guillotine be Dodged?

The is/ought problem, or dichotomy, is the idea from David Hume that one cannot get an ought (prescription) from an is (description) – one cannot determine how one ought to behave given just a description of the world. Sam Harris, in his book “The Moral Landscape” disagrees with this, arguing that values/ethics can be derived from science. Is Harris correct or misguided?

This post was motivated by watching the following video by Rationality Rules:

The argument made by Sam Harris is essentially

Premise: engaging in behavior Y will reduce the well-being of individual H (description/is)
Conclusion: H ought not engage in behavior Y (prescription/ought)

But, as the video above points out, this uses an unstated premise: “one ought not do things that reduce one’s well-being”

The issue, then is that premise 1 is a descriptive/is statement, but premise 2 is a prescriptive/ought statement, meaning that the conclusion fails to derive an ought from an is. The video above argues that this is the case because premise 2 is based on a standard or goal – that one ought to engage in actions that increase well-being and avoid engaging in actions that reduce well-being – and is therefore begging the question (the arguments premises assume the conclusion).

Here I will attempt to formulate an argument that does derive the ought “humans ought to do what maximizes well-being” only from exclusively description/is premises. Let me know if I’ve succeeded:

A)

  1. It is a fact that individual human beings, as a result of evolution by natural selection, will acquire the goal of maximizing well-being as understood by each individual
    1. Having goal-oriented actions is a necessary condition for something to be alive; in other words, “a living organism engages in goal-oriented behavior” is an analytic statement
    2. Possessing goals and the possible means of achieving them is a necessary condition for something to be conscious; in other words, “a conscious organism possesses goals and the possible means of achieving them” is an analytic statement
    3. Due to goals emerging via evolution by natural selection, those goals will necessarily include survival
    4. Survival is achieved by maximizing well-being
    5. Humans are alive, humans are conscious, and humans emerged via evolution by natural selection
    6. Therefore, humans are organisms that possess goals along with the possible means of achieving them and engage in behavior oriented toward achieving those goals, with those goals necessarily having to do with survival which is achieved by maximizing well-being
      1. Establishing this is necessary to show that A1 is a description and not a prescription, because “having the goal of maximizing well-being” is not something that can be separated out from the description of a human being (i.e. to say that “doing X is good in light of the goal of maximizing well-being”, which implies that X and the goal of maximizing well-being could be separated, is incorrect)
      2. That the goal of maximizing well-being is contingent on our evolutionary past does not make the goal any less descriptive or any more prescriptive
    7. It is a fact that individual human beings are irrational creatures (e.g. the work of Psychologists like Daniel Khaneman, Dan Ariely)
    8. Irrationality can be defined as the deviation from the “ideal” rational human (or the Econ a la Khaneman)
      1. An “ideal” rational human (or Econ) can be defined as an individual that possesses an understanding of what decisions and actions will optimally maximize the individual’s well-being
    9. Therefore, irrational individual humans will not always do what is optimal to maximize their individual well-being
      1. In other words, maximization of individual well-being does not happen simply by following one’s immediate inclinations due to those inclinations being based on imperfect conceptualizations of the means for attaining maximal well-being
      2. The distinction between “maximizing well-being” and “optimally maximizing well-being” needs to be drawn here: maximizing well-being is a goal while optimally maximizing well-being is a means of achieving the goal (it is one of multiple possible means of attempting to achieve the goal of maximizing well-being, and it is the one out of those possible ways that will optimally achieve the goal of maximizing well-being, thus it is the description of a possible way of achieving the goal of well-being)
      3. What this tells us is that if one has the goal of maximizing well-being, it does not necessarily entail that one will always make decisions and take actions that do, in fact, maximize one’s well-being (due to our irrationality, our means and our ends don’t always perfectly align), which means that the failure of individual humans to make the decisions and take the actions that do, in fact, maximize their well-being cannot be used to show that well-being is contingent on the values of a particular culture or tradition, since things like culture and tradition can be predicated on suboptimal (irrational) means of achieving well-being

B)

  1. Humans are social creatures, as a result of evolution by natural selection, acting within a society populated by other human individuals
  2. The actions of one individual does not affect only the well-being of that individual, but also affects the well-being of other individual humans within that society
  3. The actions of irrational individual humans will not always do what is optimal to maximize their individual well-being (from A4 above)
  4. Therefore, the actions of irrational individual humans do not always optimally maximize the well-being of other individuals within the society

C)

  1. Humans are a sentient species capable of using reason
    1. Capable and capacity here being defined as satisfying the necessary and sufficient conditions for some X to be utilized, even if X in actuality goes unutilized
  2. Reason can be defined as the capacity for a sentient species to discern how its own irrationality leads to diminished well-being for itself and others within the society
  3. Therefore, a human is capable of discerning how its own irrationality leads to diminished well-being for itself and others within the society

D)

  1. An essential property X of some entity H is a property that is present in some entity H in all possible worlds
    1. If H in some possible world lacks the essential property X, then that entity is not actually an H
    2. In other words, “H has the property X” is an analytic statement
  2. The capacity for reason is an essential property of the human species
    1. If in some possible world there are ‘the human species’ lacking the capacity for reason, then they would not fit the definition of the human species
    2. Therefore “humans lacking the capacity for reason” is a contradiction
  3. Therefore, the capacity for discerning how irrationality leads to diminished well-being for itself and others within the society is an essential property of the human species

E)

  1. It is a fact that individual human beings, as a result of evolution by natural selection, will acquire the goal of maximizing well-being as understood by each individual (restatement of A1)
  2. Irrational individual humans will not always do what is optimal to maximize their individual well-being (restatement of A4)
  3. The actions of irrational individual humans do not always optimally maximize the well-being of other individuals within the society (restatement of B4)
  4. A human is capable of discerning how its own irrationality leads to diminished well-being for itself and others within the society (restatement of C3)
  5. The capacity for discerning how irrationality leads to diminished well-being for itself and others within the society is an essential property of the human species (restatement of D3)
  6. Therefore, there exist possible worlds in which humans utilize their capacity (their reason) to optimize the maximization of well-being

F)

  1. There exist possible worlds in which humans utilize their capacity (their reason) to optimize the maximization of well-being (restatement of E6)
  2. The possible worlds in which humans utilize their capacity to optimize the maximization of well-being are most likely to be those possible worlds where the necessary and sufficient conditions for achieving the optimal maximization of well-being are satisfied
    1. The necessary and sufficient conditions for achieving the optimal maximization of well-being are those conditions defining ‘well-being’ that emerge within a species through evolution by natural selection
    2. The term ‘most likely’ is determined by the logic of natural selection, wherein possible worlds that do not use their capacity to optimize the maximization of well-being but still optimize the maximization of well-being (analogous to the conditional probability of an organism surviving given it does not possess some beneficial trait), or the possible worlds that do use their capacity to optimize the maximization of well-being but still have diminished well-being (analogous to the conditional probability of an organism not surviving given that it does possess some beneficial trait) are significantly rarer than the two other alternatives:
      1. Possible worlds that do not use their capacity to optimize the maximization of well-being and also have diminished well-being (analogous to the conditional probability of an organism not surviving given that it does not possess some beneficial trait)
      2. Possible worlds that do use their capacity to optimize the maximization of well-being and also have optimally maximized well-being (analogous to the conditional probability of an organism surviving given that it does possess some beneficial trait)
    3. Therefore, an individual human’s utilization of their capacity for optimizing the maximization of well-being is more likely to actualize the possible worlds with optimally maximized well-being

G)

  1. It is a fact that individual human beings, as a result of evolution by natural selection, will acquire the goal of maximizing (the state of affairs of) well-being as understood by each individual (restatement of A1)
  2. An individual human’s utilization of their capacity for optimizing the maximization of well-being is more likely to actualize the possible worlds with optimally maximized well-being (restatement of F3)
  3. A goal can be defined as a desire to actualize a state of affairs (such as maximal well-being)
  4. Therefore, if maximized well-being is a goal for humans (G1) and utilizing the capacity to optimally maximize well-being is more likely to actualize the desired state of affairs maximized well-being (G2), then humans ought to utilize their capacity for optimizing the maximization of well-being
    1. In other words, since it is the goal to maximize well-being (from G1) and it is more probable to achieve maximal well-being using reason, then by modus ponens in the conditional G3, when confronted with ethical dilemmas, humans ought to use reason in determining which choice will optimally maximize well-being for themselves and for others within society

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