My friend states that 'morality is subjective' since one can construct definitions based on arbitrary intensions and extensions of a well-defined set viz. 'My own morally not bad actions' from the universal set 'U=set of acts that can be done by humans'.

My doubt: I feel that 'morality is subjective' is again a moral position, is it an objective view? How can we say that the set 'U=set of acts that can be done by humans' is well-defined? Especially the term 'acts'.

If one can tweak definitions, particularly using set-theoretic approaches to morality, then, how does one deal with the conflicts that arise from this conflicts such as trying to include 'Believe in god' as an action in this well-defined set U? It seems that crafting some sort of categorical imperative is problematic.

Is it even possible to define a set U of acts done by humans is moral and then discriminate which activities are in and out of the set?

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    Do you really think that we can "apply" set theory to ethics? May 10, 2022 at 5:55
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    And what does it mean "what is the problem with constructing a set namely 'True statements' to include 'Math does not exist'?" Do you mean that the set of all true statements must include also the statement "Math does not exist"? But math exists: it is a human activity that produce "tangible" evidences: universities, teachers, books, congresses,... May 10, 2022 at 6:43
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    And about the "collection" (not set in the mathematical sense) of all acts that can be done by humans, how can we define it? by enumeration? Of course, your own actions will belong to that "collection", whatever it means. May 10, 2022 at 6:45
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    Maybe more useful Constructivism in Metaethics. May 10, 2022 at 6:49
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    @MauroALLEGRANZA, I believe you misunderstood the question. The question was critical of the argument for the subjectivity of morality, not supporting it. And the comment about a set containing the statement "math does not exist", while awkward and not quite analogous, was (I believe) intended to refute the original argument for the subjectivity of morality by showing that a similar argument could be used against mathematics. May 10, 2022 at 7:30

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The difficulty with this position is that the concept of morality always has an aspect of mutuality. We are not moral in ourselves, we are moral towards others. A person alone on a desert island has no need of morality; morality under such conditions is an affectation, at best.

This means that morality is intersubjective, not purely subjective. To put that in set-theoretical terms, we cannot arbitrarily choose actions from the universal set of potential human actions (which is a perfectly fine, if infinite, set construction). We must choose those actions that are tolerable to those around us, as those around us must choose actions tolerable to us. Otherwise we will find ourselves in conflict, or even cast out of human association and all the benefits such provides.

Moral behavior is neither open-ended and subjective nor objectively fixed. It is constrained, bounded, and recursively defined.

  • Is there a contradiction in saying ''I agree this 'Arbitrary morality' guides human being, but I will oppose and possibly wont allow any one to do 'wrong' in my morality''?
    – Messi Lio
    May 13, 2022 at 8:05

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