Christian von Ehrenfels Quote

Not all desired things are valuable, but rather only those which are worthy of being desired. Whether this worthiness belongs to a thing, however, is not in the particular case yielded from the investigation of the objective nature of the thing, but rather from the subjective consideration of the desire directed at the thing. From the examination of our own mental activity in the act of desire we discern whether this is directed at something valuable or not.

Christian von Ehrenfels (1897, 3–4), as cited in: Robin Rollinger and Carlo Ierna, "Christian von Ehrenfels", The Stanford Encyclopedia of Philosophy, Winter 2016 Edition, Edward N. Zalta (ed.)