I'm having a hard time to distinguish "necessary and sufficient" in this case.

I think it's necessary. For bread to exist, all the above elements are necessary.

I also think that is sufficient. Just have these elements that bread comes up.

Am I right?

  • 1
    If you examine what is necessary and sufficient for bread you'll find it's the whole universe, including its entire history. Anything less will be insufficient. You haven't even included the baker, the sunshine, the soil, the earth-worms and the microbes, and not even the Big Bang.
    – user20253
    Sep 10, 2017 at 11:32
  • PeterJ, You are right that those things are necessary for bread. But that's a misapplication of the term as its used in philosophy. See below. Sep 10, 2017 at 13:59
  • This question has been asked many times before; the question I linked to has a general explanation. If there is something concretely that you don't understand in that, could you please clarify where exactly in applying the definitions you get stuck?
    – user2953
    Sep 11, 2017 at 10:44
  • @ChristopherE - You speak of the definition of 'bread' and what is necessary to meet it. I'm speaking of what makes bread possible. If you gave a full definition of bread it would refer to space-time, consciousness, stars and planets and so on. The OP asks about the causes for the existence of bread, not how bread is defined. I take your point but don't think it quite answers the question. I have no method for distinguishing between conditions and causes and I rather doubt there is one unless it is arbitrary.
    – user20253
    Sep 11, 2017 at 13:02
  • @PeterJ, Yes, and the OP/question pretty straightforwardly displays a confusion about how the terminology of nec & suf conditions are used by philosophers. Unlike causes, nec & suf conditions are not relationships between events or states of affairs; they are relationships between statements/sentences/propositions (or similar, depending on your theory of meaning). Sep 12, 2017 at 1:27

3 Answers 3


I think where you're getting mixed up is that there are different kinds of conditions. Normally, when philosophers discuss necessary and sufficient conditions, they mean for the application of a predicate to an individual. For example, What conditions are necessary and sufficient for X (some individual) to be bread (where "being bread" is a predicate). Equivalently: under what conditions, for any X, does X count as bread?

Another kind of condition is causal or circumstantial. This is the kind of condition one means if one asks, what conditions are necessary for fire to start? What conditions are sufficient. When the original question (and Heinrich's answer and PeterJ's comment) discuss conditions, they mean what conditions are necessary for bread to come about, for bread to exist? That is different.

The first (definitional) kind of condition concerns when a predicate can properly be applied to a thing. The second (causal) kind of condition concerns when something can exist.

I am not a baking expert, but to give necessary and sufficient conditions for X being bread, we can say something like:

For X to be bread, it is necessary that it:

  • be made with flour;
  • be made with water;
  • be made with a leavening agent;
  • have its ingredients mixed;
  • have its ingredients baked.

Each of these predicates is individually necessary for being bread. That means that a thing can't be bread if it lacks any one of them.

These predicates are also jointly sufficient for being bread. That means that anything that meets all of them is bread.

However, there are also many other conditions not on this list which are sufficient for being bread. Being Wonderbread is a sufficient condition for being bread. Being sourdough bread is a sufficient condition for being bread. Being a bagel is sufficient condition for being bread. And so on.

  • I learned it the as cause, necessary cause, sufficient cause. It's the old fashioned way I guess. We want our kids to know that oranges don't come from the supermarket. Whatever way helps to do that I'm for it, maybe both of them do, or not.
    – Gordon
    Sep 10, 2017 at 16:11
  • 1
    Gordon, yes, but in that terminology “cause” is not restricted to “material cause,” which is generally how we use “cause” in modern English. Sep 10, 2017 at 16:13
  • Thank you. I need to go back and review this myself, taking into consideration what you have written. It's possible that I never properly understood this subject!
    – Gordon
    Sep 10, 2017 at 16:18
  • "Each of these predicates is individually necessary for being bread." And together?
    – Devanil
    Sep 10, 2017 at 21:10
  • @Devanil Together, necessary. Sep 12, 2017 at 2:00

Water is necessary but not sufficient.

Wheat is necessary but not sufficient.

Salt is necessary (for many tastes) but not sufficient.

Baking is necessary but not sufficient.

Water + Wheat + Salt + Baking, is sufficient for bread.

(Some sour dough would improve the bread but is not necessary.)


Something is necessary if, without it, it is impossible to arrive at the outcome.

Something is sufficient if you can arrive at the outcome with only that thing or things.

Unfortunately, your example isn't great because there are so many varieties of bread and breadmaking is a relatively complex process.

For example, it's perfectly possible (and quite common) to make bread without wheat or salt so neither are necessary.

Also, imagine you plonked water, wheat and salt on a plate and put it in the oven for 3 days. It would be a stretch to call the resulting concoction bread. As such, it cannot be correct that these inputs are sufficient.

  • This seems correct to me.
    – user20253
    Sep 12, 2017 at 9:24

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