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Is "ought" derived from "is"?

Some philosophers claim that we can derive what we ought to do based on what is. Others claim that ought-statements and is-statements belong to separate realms, and that there is ultimately no justification for what we ought to do based on what is.

Implications to Other Questions

Is morality objective?
Is "ought" derived from "is"?

Experts and Influencers

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Experts In Philosophy

Ayn Rand    Philosopher, Novelist
In answer to those philosophers who claim that no relation can be established between ultimate ends or values and the facts of reality, let me stress that the fact that living entities exist and function necessitates the existence of values and of an ultimate value which for any given living entity is its own life. Thus the validation of value judgments is to be achieved by reference to the facts of reality. The fact that a living entity is, determines what it ought to do.
01 Nov 1964    Source

Experts In Science

Robin Hanson    Economics Professor
Mostly Agree
...there is an important sense in which most attempts to derive “ought” are built on “is.” ... most every attempt to derive an “ought” is based ultimately on “is” claims about the reliability of our intuitions about such more basic “ought” claims. If we can’t find a coherent way to integrate these “is” claims with the rest of our network of reasonable “is” claims, then we can’t argue coherently for such “ought” claims at all.
12 Dec 2009    Source

Experts In Atheism

Sam Harris    Writer, Speaker, Atheism Activist
Mostly Agree
So, while it is possible to say that one can't move from "is" to "ought," we should be honest about how we get to "is" in the first place. ... What evidence could prove that we should value evidence? What logic could demonstrate the importance of logic? ... So it is with the linkage between morality and well-being...
07 May 2010    Source

Experts In Philosophy

Peter Singer    Philosophy Professor
No definition of morality can bridge the gap between facts and action. [But] disputes over the definition of morality and over the "is-ought" problem are disputes over words...
01 Jan 1973    Source

Experts In Science

Richard Feynman    Nobel Laureate in Physics
...I believe that moral questions are outside of the scientific realm. ... The typical human problem, and one whose answer religion aims to supply, is always of the following form: Should I do this? Should we do this? Should the government do this? To answer this question we can resolve it into two parts: First — If I do this, what will happen? – and second – Do I want that to happen? ... Now a question of the form: If I do this, what will happen? is strictly scientific. [The second is not.]
02 May 1956    Source

Paul Z. Myers    Biology Professor
Sam Harris recently and infamously proposed that, contra Hume, you can derive an 'ought' from an 'is', and that science can therefore provide reasonable guidance towards a moral life. ... I don't think Harris's criterion — that we can use science to justify maximizing the well-being of individuals — is valid. We can't. We can [only] use science to say how we can maximize well-being... Harris is smuggling in an unscientific prior in his category of well-being.
04 May 2010    Source


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0 Points      dionisos      22 Aug 2016      Stance on Question: Disagree
The same than blacktrance.

0 Points      TZX      16 Feb 2011      Stance on Question: Mostly Disagree
At best we can derive "how to" from "is". "Ought" is "how to" with desire towards its result.

0 Points      blacktrance      11 Feb 2011      Stance on Question: Disagree
"Is" claims are claims about reality. "Ought" claims are statements of preference. While "ought" is dependent on "is", "is" does not imply "ought".

1 Point      Tordmor      09 May 2010      Stance on Question: Mostly Agree
The term "ought" implies that there exists some measure of moral quality of your action that is independent from the subject, otherwise the term would make no sense since a conversation about what one person "ought" to do implies a judgment by some other person. If I ask someone what I ought to do I subject my own actions to his judgment. If someone else tells me what I ought to do he assumes this judgment and even if I merely state what I ought to do I present this statement to be judged as true or false to someone else.

Therefore if no basis outside of an individual existed to judge his actions as moral or immoral the term "ought" would be meaningless. Or to put it the other way round: If the term "ought" has any meaning at all it must be based on some "is".

This being said, whether or not the term "ought" does in fact have any meaning is open to debate. I like Ayn Rand's take on it who said, that since any valuation requires the valuer to be alive, life must be an objective value. One could therefore derive the "ought" from what is or is not supporting of life. That is, however, based on a generalization from one individual life to human life in general which might be a weakness.

1 Point      the27th      09 May 2010      Stance on Question: Mostly Disagree
No; people with equal knowledge about the world disagree on first principles of morality. "Is" can never tell you what to value.

"Is" statements can tell you when you're factually mistaken and need to update your morality to keep it consistent -- that is, if you believe in preserving human life, learning about the existence of genocide in Burma will make you more concerned with ending it. If you value human life to begin with, then you should value Burmese life. But if you don't value human life, no "is" statement can persuade you to.

0 Points      Benja      08 May 2010      General Comment
Many claims that we ought to act in a particular way are based on claims about how the world is. For example, the Catholic Church uses several is-claims that underpin their ought-claim on abortion:

"The Church teaches that every spiritual soul is created immediately by God - it is not 'produced' by the parents - and also that it is immortal: it does not perish when it separates from the body at death, and it will be reunited with the body at the final Resurrection."

And due to motivated cognition, once we think the world ought to be a particular way, we let that affect how we think the world is. Mohammed Yusuf:

"If it runs contrary to the teachings of Allah, we reject it. We also reject the theory of Darwinism."

The great thing about this philosophical question, like so many philosophical questions, is appreciating the question, rather than having the "right" answer. If you've never thought about the question, then what you think ought to be and what is, is likely to be indiscriminately intertwined. Simply trying to answer the question - no matter what answer you come to - clarifies your world view.