Plutarch Quaestiones Convivales 4.4.3

[3] But, says Symmachus, I will go more seriously to work, and more like a logician. For if that may truly be said to be a dainty which gives meat the best relish, it will evidently follow, that that is the best sort of dainty which gets men the best stomach to their meat. Therefore, as those philosophers who were called Elpistics (from the Greek word signifying hope, which above all others they cried up) averred that there was nothing in the world which concurred more to the preservation of life than hope, without whose gracious influence life would be a burden and altogether intolerable; in the like manner that of all things may be said to get us a stomach to our meat, without which all meat would be unpalatable and nauseous. And among all those things the earth yields, we find no such things as salt, which we can have only from the sea. First of all, there would be nothing eatable without salt, which mixed with flour seasons bread also. Hence it was that Neptune and Ceres had both the same temple. Besides, salt is the most pleasant of all relishes. For those heroes who, like champions, used themselves to a spare diet, banishing from their tables all vain and superfluous delicacies, to such a degree that when they encamped by the Hellespont they abstained from fish, yet for all this could not eat flesh without salt; which is a sufficient evidence that salt is the most desirable of all relishes. For as colors need light, so tastes need salt, that they may affect the sense, unless you would have them very nauseous and unpleasant. For, as Heraclitus used to say, a carcass is more abominable than dung. Now all flesh is dead, and part of a lifeless carcass; but the virtue of salt, being added to it, like a soul, gives it a pleasing relish and poignancy. Hence it comes to pass that before meat men use to take sharp things, and such as have much salt in them; for these beguile us into an appetite. And whoever has his stomach sharpened with these sets cheerfully and freshly upon all other sorts of meat. But if he begin with any other kind of food, all on a sudden his stomach grows dull and languid. And therefore salt doth not only make meat but drink palatable. For Homer’s onion, which, he tells us, they were used to eat before they drank, was fitter for seamen and boatmen than kings. Things moderately salt, by being agreeable to the mouth, make all sorts of wine mild and palatable, and water itself of a pleasing taste. Besides, salt creates none of those troubles which an onion does, but digests all other kinds of meat, making them tender and fitter for concoction; so that at the same time it is sauce to the palate and physic to the body. But all other sea-food, besides this pleasantness, is also very innocent; for though it be fleshly, yet it does not load the stomach as all other flesh does, but is easily concocted and digested. This Zeno will’ avouch for me, and Crato too, who confine sick persons to a fish diet, as of all others the lightest sort of meat. And it stands with reason, that the sea should produce the most nourishing and wholesome food, seeing it yields us the most refined, the purest, and therefore the most agreeable air.