 The account just given of the distinction between intrinsic and extrinsic value is rough, but it should do as a start. Certain complications must be immediately acknowledged, though. First, there is the possibility, mentioned above, that the terms traditionally used to refer to intrinsic value in fact refer to more than one concept; again, this will be addressed later (in this section and the next). Another complication is that it may not in fact be accurate to say that whatever is intrinsically good is nonderivatively good; some intrinsic value may be derivative. This issue will be taken up (in Section 5) when the computation of intrinsic value is discussed; it may be safely ignored for now. Still another complication is this. It is almost universally acknowledged among philosophers that all value is “supervenient” or “grounded in” on certain nonevaluative features of the thing that has value. Roughly, what this means is that, if something has value, it will have this value in virtue of certain nonevaluative features that it has; its value can be attributed to these features.  For example, the value of helping others in time of need might be attributed to the fact that such behavior has the feature of being causally related to certain pleasant experiences induced in those who receive the help. Suppose we accept this and accept also that the experiences in question are intrinsically good. In saying this, we are (barring the complication to be discussed in Section 5) taking the value of the experiences to be nonderivative. Nonetheless, we may well take this value, like all value, to be supervenient on, or grounded in, something. In this case, we would probably simply attribute the value of the experiences to their having the feature of being pleasant. This brings out the subtle but important point that the question whether some value is derivative is distinct from the question whether it is supervenient. Even nonderivative value (value that something has in its own right; value that is, in some way, not attributable to the value of anything else) is usually understood to be supervenient on certain nonevaluative features of the thing that has value (and thus to be attributable, in a different way, to these features).