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  • Writer's pictureDeric Hollings

The Is-Ought Problem

Updated: Jul 8, 2023

Scottish Enlightenment philosopher David Hume is credited with having proposed the is-ought problem, also referred to as the is-ought gap, Hume’s law, and Hume’s guillotine. His formula addresses moral or values-based judgements contrasted with non-moral or facts-based observations.

Considering this matter, one source poses the question, “How do descriptive statements (an ‘is’ statement) so quickly turn into prescriptive statements (a ‘should’ statement)?” In a blog entry entitled Description vs. Prescription, I address the difference between descriptive and descriptive statements.

Practicing Rational Emotive Behavior Therapy (REBT), I assist clients with understanding how their should, must, and ought-type statements often serve as self-disturbing prescriptions of the world. We cannot use moral justification for behavior based on facts about the world.

For example, it’s a fact that everyone you’ve ever known, currently know, and ever will know will die. However, simply because you don’t want this to happen, it would be irrational to state that no one should, must, or ought to die. Life and death is as it is, not as you think it ought to be.

As one source claims, “[T]here is no theoretical connection between facts about the world and ethical facts.” We may wish that death weren’t real, prefer that one would ever die, or like it better if our loved ones could live longer. However, we cannot command reality with our desires.

Though we may think otherwise, one source accurately states “it is not obvious how one can coherently move from descriptive statements to prescriptive ones.” Still, this doesn’t stop many people from violating Hume’s principle.

As an example, one can describe how supposed “extreme conservatives” apparently behave, though one cannot accurately prescribe that others “should take that very, very seriously.” It’s unreasonable to demand that everyone share the same moral or ethical perspectives.

Hume cautioned that “reason alone can never be a motive to any action of the will’ and that by itself it can never oppose a passion in the direction of the will.” We simply cannot use moralistic reasoning to impose our will upon others.

As an example, suppose I make the declaration that no one should use hate speech, because I subjectively believe it’s a moral bad to do so. I could use a reasonable argument to justify what I think ought not to be.

One source states, “[H]ate speech is any form of expression through which speakers intend to vilify, humiliate, or incite hatred against a group or a class of persons on the basis of race, religion, skin color sexual identity, gender identity, ethnicity, disability, or national origin.”

Using the aforementioned definition of hate speech, I may formulate the following logical syllogism:

Premise 1: Anyone who expresses hatred against Jewish people is a bad person.

Premise 2: John Doe expresses hatred against Jewish people.

Conclusion: Therefore, John Doe is a bad person.

My subjective description about who is and isn’t bad may be based on a definition with which others disagree. Nonetheless, I may consider myself a decent person by opposing anti-Semitic speech. I could then develop an additional logical principle:

Premise 1: People ought not to use anti-Semitic hate speech, because it’s harmful to do so.

Premise 2: John Doe uses anti-Semitic hate speech.

Conclusion: Consequently, Joe Doe is harmful.

My logic is sound, though I’ve committed a moralistic fallacy by declaring something “bad” and “harmful.” This relates to the is-ought problem, as I’ve prescribed how others ought to behave based on my subjective and irrational demands.

I may be emphatically opposed to anti-Semitic or hateful speech, though I cannot rigidly demand others to accept my premises or cater to my stipulations—at least not in the United States. I have no right to infringe upon another person’s right to free speech simply because I don’t like what’s being said.

I consider Hume’s is-ought problem a valuable tool when helping clients to understand what drives their behavior. Perhaps you, too, will find this philosophical device useful.

If you’re looking for a provider who works to help you understand how thinking impacts physical, mental, emotional, and behavioral elements of your life—demonstrating how illogical and irrational thinking may not serve you well—I invite you to reach out today by using the contact widget on my website.

As a psychotherapist, I’m pleased to help people with an assortment of issues ranging from anger (hostility, rage, and aggression) to relational issues, adjustment matters, trauma experience, justice involvement, attention-deficit hyperactivity disorder, anxiety and depression, and other mood or personality-related matters.

At Hollings Therapy, LLC, serving all of Texas, I aim to treat clients with dignity and respect while offering a multi-lensed approach to the practice of psychotherapy and life coaching. My mission includes: Prioritizing the cognitive and emotive needs of clients, an overall reduction in client suffering, and supporting sustainable growth for the clients I serve. Rather than simply helping you to feel better, I want to help you get better!

Deric Hollings, LPC, LCSW


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