Lecture 9 — The nature of flavor

However many flavors show up in fruits, these exist also in earth.

Therefore many of the ancient students of nature say that water is of the same kind as whatever earth it passes through. This is most evident in salty water, for salt is a kind of earth. And that which is filtered through ash, which is bitter, produces a bitter flavor. There are also many springs, some bitter, some sharp-tasting, and others with every other kind of flavor.

And so it is reasonable that the genus of flavors is produced especially in growing things.

For the moist is naturally affected by its contrary, as are other things, and the contrary is the dry. Therefore it is also affected in some way by fire, for the nature of fire is dry. And heat is proper to fire and dryness to earth, as was said in the discussion of elements.

As fire, then, and as earth, they by nature neither act nor are affected at all; nor is this the case with anything else. Rather, they act and are acted on inasmuch as there is contrariety in each of them.

Accordingly, just as those who soak colors and flavors in moisture make the water be of the same kind, nature does likewise with the dry and earthen: by filtering the moist through what is dry and earthen, and by changing it through heat, it makes the moist be of a certain quality.

And this is flavor: an affection caused in moistness by the dryness just mentioned, an affection capable of changing the sense of taste in potentiality to actuality.

For it brings the sensitive part which already exists in potentiality to this. For sensing is not like learning, (“Learning” translates the term discere on which Aquinas comments, but at this point in the Aristotelian text Gauthier provides the manuscript corruption dicere (“speaking”).) but contemplation.

Now we must take it that flavors are affections or privations not of every kind of dryness, but only the kind that nourishes, because it is neither dryness without moistness nor moistness without dryness. For food for animals is not one simple thing, but something mixed. Neither is food for plants: it is something mixed.

Of the sensible qualities of the food provided to animals, the objects of touch are what produce growth and diminution: for the cause of these is the heat and cold that is provided, for these produce growth and diminution. But what is provided nourishes according as it is an object of taste: for everything is nourished by sweetness, whether it is simple or mixed.

We must determine about these points in the discussion of generation, but touch on them now as far as is necessary. Heat augments, and it prepares nourishment, because it draws out what is light, but leaves what is bitter and salty because of its weight. Thus what the external heat does in external bodies is what the heat in the nature of animals and plants does. Therefore they are nourished by sweetness.

But other flavors, like spicy and sharp, are mixed into food for seasoning. And they are for opposing, because sweetness is excessively nourishing, and floating.

129. However many flavors (441a30). After the Philosopher has eliminated opinions of others on the cause of the origin of flavors, here he gives the true cause according to his own opinion. On this point, he does three things.

First, he gives the cause of the generation of flavors.

Second, he defines flavor, where he says and this is flavor (441b19; [141]).

Third, he clarifies something he said, where he says now we must take it that flavors are affections (441b23; [143]).

On the first point, he does three things.

First, he shows that flavors pertain to earth, and not only, as the ancients held, water.

Second, he shows that water is changed with respect to flavors by dryness of earth, where he says for the moist is naturally affected (441b8; [133]).

Third, he concludes to the cause of generation of flavors, where he says accordingly, just as those who soak colors (441b15; [140]).

On the first point, he does two things.

First, he proposes what he intends.

Second, he clarifies the proposal, where he says therefore many of the ancient students of nature (441b1; [130]).

Accordingly, he first says that all flavors that show up in fruits of plants, in which flavors are clearly differentiated, are also present in earth. Not that pure earth has flavor, for it has no moisture: but with a small admixture of moisture, together with an alteration caused by heat, it does acquire a flavor.

130. Then, when he says therefore many of the ancient students of nature (441b1), he clarifies what he said by means of two signs.

The first is taken from a saying on which many of the ancient natural philosophers agree, namely those who say that water is of the same kind of flavor as the earth it passes through. This is most evident in salty water: not that of the sea itself, for that has another cause, as was shown in the book, The Meteorology; (Aristotle, Meteorology 2.2, 354b18–33, 355a32–b6; 2.3, 357a5–358a27; cf. Aquinas, Commentary on Meteorology, bk. 2, lect. 5–6.) rather, this is evident because the waters of certain springs are salty, having passed through earth that is similar. This should not seem surprising, because salt is a kind of earth, as are alum and sulfur; thus some mountains are made of salt. The point is also clear in the case of waters filtered through ash, which have a bitter flavor, as does the ash through which they are filtered. And there are also springs of different flavors because of the different kinds of earth through which they pass.

131. It should be considered that Aristotle does not introduce this point to show the universal cause of the generation of flavors, because it only clarifies the cause of flavors in water. Rather, he introduces all this as a sign to show that flavors pertain to earth, and not only to water.

132. He presents the second sign where he says and so it is reasonable (441b7). He says that because flavors pertain to earth, it is reasonable that the genus of flavors is most evident and most various in what grows directly out of the earth, because of the affinity of such things with earth.

133. Then, when he says for the moist is naturally affected (441b8), he proves that moisture of water is changed with respect to flavors by earth.

First, he proves the proposition.

Second, he eliminates an obstacle, where he says as fire, then (441b12; [135]).

Accordingly, he first says that the moist is naturally affected by its contrary, just as all other things are also affected by their contraries, as was proved in On Generation 1. (Aristotle, On Generation and Corruption 1.7, 323b29–324a19; cf. Aquinas, Commentary on Aristotle’s On Generation and Corruption, bk. 1, lect. 19–20.) But what is contrary to the moist is the dry. Hence the moist is naturally affected by the dry. And because not only earth is dry, but also fire, the moist is also affected by fire.

Now although two of the four elemental qualities belong to each individual element—fire is hot and dry, air is hot and moist, water is cold and moist, earth is cold and dry—each individual quality is in one individual element principally, as proper to that element.

134. Heat is proper to fire, for because fire is the noblest of the elements and the one closest to the heavenly body, what belongs to it properly and of itself is heat, which is the most active quality. Dryness belongs to fire because of the extremity of the heat: the moistness is as it were consumed.

Heat belongs to air secondarily because of the latter’s affinity with fire. What belongs to air of itself is moistness, which is the nobler of the passive qualities. The heat as it were dissolves the moistness, but does not completely consume it, because of air’s greater distance from the first cause of heat, the heavenly body.

What properly and of itself belongs to water is cold, which is the second active quality, being as it were privatively related to heat. What belongs secondarily to water is moistness, in keeping with the nearness of water to air.

Cold belongs to earth secondarily, because of earth’s nearness to water, as it were. Dryness belongs properly and of itself to earth: because of earth’s very great distance from the source of heat, as it were, it is not dissolved into moistness, but remains at the extreme of density.

These points were determined in the book on elements—that is, in On Generation 2. (Aristotle, On Generation and Corruption 2.3, 330a30–331a6; cf. Aquinas, Commentary on Aristotle’s On Generation and Corruption, bk. 2, lect. 2–3.) Hence the moist is by nature most affected by dryness of earth.

135. Then, when he says as fire, then (441b12), he eliminates an obstacle. It does not follow that the moist is more affected by a greater dryness unless it is affected by dryness as dryness. But someone might deny this by saying that the moist is most affected by fire as fire.

So to eliminate this, he says that fire, as fire, by nature neither acts nor is affected at all; nor is this the case with any other body. He proves this as follows. Things by nature act and are affected by one another according as they have contrariety, as was shown in On Generation 1. (Aristotle, On Generation and Corruption 1.7, 323b29–324a19.) But nothing is contrary to fire inasmuch as it is fire, or to earth inasmuch as it is earth, or to any substance. Hence it remains that these bodies do not act and are not affected inasmuch as they are fire or earth or any such thing, but inasmuch as they are hot and cold, moist and dry.

Difficulties

I

But against this there seems to be a difficulty.

136. If it belongs to fire of itself to be hot and dry, then, if fire acts inasmuch as it is hot, it seems to follow that it acts inasmuch as it is fire.

On this point it must be known that some thought that heat is the substantial form of fire, and according to this position, fire will have a contrary according to its substantial form, and consequently will be active according to it. But because “fire” signifies not the form alone, but the composite of matter and form, it is said in the text that fire is not active and that there is nothing contrary to it. This is how Alexander solves the difficulty in the commentary. (Alexander of Aphrodisias, On Aristotle’s “On Sense Perception,” trans. Alan Towey, pp. 74–75.)

But this cannot stand, because the same thing cannot be in the genus of substance and that of accident, according to the Philosopher’s remark in Physics 1: what truly is does not become an accident of anything. (Aristotle, Physics 1.3, 186b4–5; cf. Aquinas, Commentary on Physics, bk. 1, lect. 6.) But substantial form is reduced to the genus of substance. Hence it cannot be that heat is the substantial form of fire, since it is an accident of other things.

Again, substantial form is perceived not by sense but by intellect, for “what something is” is the proper object of intellect, as is said in On the Soul 3. (Aristotle, On the Soul 3.4, 429b5–22; 3.6, 430b27–28l cf. Aquinas, Commentary on Aristotle’s On the Soul, bk. 3, lect. 2, nn. 717–18; lect. 5, n. 762.) Hence, since heat is something sensible per se, it cannot be the substantial form of a body.

137. Therefore it must be said that heat per se is present in fire not as its substantial form, but as its proper accident. And because natural action belongs to a contrary that causes alteration, fire acts according to its heat, to which there is something contrary, and not according to its substantial form, which has no contrariety.

This is unless “contrariety” is taken in a wide sense with respect to the difference between perfect and imperfect in the same genus. In this sense contrariety is also found in numbers according as a smaller number stands as something imperfect, and a part, in relation to a larger one. The substantial forms of things are like numbers, as is said in Metaphysics 8. (Aristotle, Metaphysics 8.3, 1043b32–1044a11; cf. Aquinas, Commentary on Metaphysics, bk. 8, lect. 3, 1723–24.) And in this sense there is also contrariety between the differences of any genus, as is said in Metaphysics 10, for thus animate and inanimate, and sensible and insensible, are contraries. (Aristotle, Metaphysics 10.8, 1058a8–16; cf. Aquinas, Commentary on Metaphysics, bk. 10, lect. 5, nn. 2032–35.)

II

But there still might be a difficulty.

138. For if the principle of action in the elements is not substantial, but accidental, form, then, since nothing acts beyond its own nature, it does not seem that matter is changed by the natural action of the elements with respect to substantial form, but only with respect to accidental form.

For this reason some held that all substantial forms are from a supernatural cause, and that a natural agent merely disposes to a form by altering. (Gauthier, p. 55, indicates that Avicenna is meant, with reference to the following: Aquinas’s Summa contra gentiles III.69, ST I.115.1, and Questions on the Virtues, q. 8; Averroes’ commentary on the Metaphysics (7.31; 11[12].18); and Avicenna’s own statements in Avicenna Latinus. Liber de philosophia prima 5–10, ed. S. Van Riet, Louvain-Leiden: E. Peeters, 1980, tr. 9, ch. 5, lines 29–48 (pp. 489–90) and lines 94–95 (p. 493).) This reduces to an opinion of the Platonists, who held that separate forms are the cause of generation and that all action is from an incorporeal power. On the other hand the Stoics, as Alexander says, held that bodies act of themselves, that is, inasmuch as they are bodies. (Alexander of Aphrodisias, On Aristotle’s “On Sense Perception,” trans. Alan Towey, p. 74.) But Aristotle here holds the middle way, which is that bodies act according to their qualities.

139. And so it must be said that each thing acts according as it is a being (ens) in actuality, as is clear from On Generation 1. (Aristotle, On Generation and Corruption, 1.9; cf. Aquinas, Commentary on Aristotle’s On Generation and Corruption, bk. 1, lect. 23. Gauthier, p. 55, points out that this axiom might be constructed on the basis of On Generation and Corruption, 1.5, 320b17–19, and notes that it is common in Aquinas’s works.) But just as the being (esse) of elemental qualities is derived from their essential principles, so, necessarily, power of acting also belongs to such qualities from the power of the substantial forms. But everything that acts by the power of something else produces something like that in the power of which it acts: for instance a saw makes a house by the power of the house that is in the soul; and natural heat generates animate flesh by a power of soul. And it is also in this way that matter is changed by the action of elemental qualities with respect to substantial form.

140. Then, when he says accordingly, just as those who soak colors (441b15), he concludes from the foregoing to the generation of flavors. He says that just as those who soak colors and flavors—that is, colored and flavored bodies—in moisture of water make the water be of the same kind of color and flavor, so, conversely, when moistness of water is filtered through dryness of earth, and at the same time there is a change caused by heat digesting the moistness, and making a kind of mass of moistness with dryness, then the moistness of water becomes qualified by a flavored quality.

141. Then, when he says and this is flavor (441b19), he introduces a definition of flavor on the basis of the foregoing. He says that flavor is nothing but an affection caused in moistness of water by the dryness mentioned—that is, dryness of earth—with addition of heat; an affection that, by changing the sense of taste in potentiality, brings it to actuality. This last part is added to differentiate odor from other affections that are caused by moistness and dryness through action of heat, but that alter not taste, but other senses.

142. Then, when he says for it brings the sensitive part (441b21), he clarifies the definition of flavor just stated with respect to its last part. For the first part is clear from the foregoing; but he said that flavor alters the sense of taste “in potentiality.”

To clarify this he adds that flavor, like any sensible object, brings to actuality the sensitive part, which previously was in potentiality to the sensible object, because sensing, which follows from the action of a sensible object on a sense power, is not like learning, but contemplation. That is, it is unlike what learning is, because a habit of science is newly produced in one who learns, but a sense power is not newly produced by the action of the sensible object in one who senses: rather, the sense power is made operative in actuality, which is like what happens in one who contemplates in actuality.

143. Then, when he says now we must take it that flavors are affections (441b23), he clarifies something he said above, namely that flavor is not only in moistness or in dryness. On this point, he does three things.

First, he shows that flavor is based on the moist and the dry together.

Second, he proves something he presupposed, where he says of the sensible qualities (441b27; [144]).

Third, he clarifies the proof, where he says we must determine (442a3; [146]).

Accordingly, he first says that flavors are affections—with respect to sweet—or privations—with respect to bitter, which is related to sweet as black is to white, that is, as something imperfect and a privation—not of just any dryness, but of nourishing dryness—that is, the dryness by which animals or plants can be nourished. From this we can take it that neither dryness without moistness nor moistness without dryness pertains to flavor, because the food by which animals are nourished is not what is just moist or dry, but something mixed from these. For we are nourished by the same things out of which we are composed, as was said in On Generation 2. (Aristotle, On Generation and Corruption, 2.8, 335a10–11; cf. Aquinas, Commentary on Aristotle’s On Generation and Corruption, bk. 2, lect. 8.) And the argument is the same in the case of plants.

144. Then, when he says of the sensible qualities (441b27), he proves something he presupposed, namely that flavor is an affection or privation in nourishment.

Here it must be considered that the food that is provided to animals serves them for two purposes, namely growth, by which they are brought to perfect size, and nourishment, by which their substance is preserved. Food also serves them for generation, but this no longer pertains to the individual, but the species.

Accordingly, he says that the food provided to animals, being sensible objects inasmuch as they are objects of touch, cause growth and diminution, because heat and cold cause growth and diminution: heat properly causes growth, for it belongs to heat to expand and spread out, moving, as it were, towards a circumference; cold causes diminution, because it belongs to cold to constrict, moving, as it were, towards a center. Hence animals grow in youth and shrink in old age.

145. The remark in On the Soul 2 that food causes growth inasmuch as it is quantitative does not contradict this, because quantity would not suffice for growth if there were not heat to convert and digest it. (Aristotle, On the Soul 2.4, 416b12–13; cf. Aquinas, Commentary on Aristotle’s On the Soul, bk. 2, lect. 9, n. 343.) But the food provided nourishes inasmuch as it is an object of taste.

He proves this as follows: everything is nourished by sweetness, which is perceived by taste, whether by simple sweetness or by sweetness mixed with other flavors. And the remark of On the Soul 2 that touch is the sense of food does not contradict this, because there he places moisture—that is, flavor—among the objects of touch, and in the same place, he says that flavor is the pleasurable in food inasmuch as it indicates suitability of food. (Aristotle, On the Soul 2.3, 414b7; cf. Aquinas, Commentary on Aristotle’s On the Soul, bk. 2, lect. 5, n. 290.)

146. Then, when he says we must determine (442a3), he confirms the foregoing proof.

First, inasmuch as he said that everything is nourished by sweetness.

Second, inasmuch as he said something about admixture of other flavors, where he says but other flavors (442a8; [147]).

Accordingly, he first says that we must determine what pertains to growth and nourishment in the discussion of generation. He said something about this in the book On Generation in general, (Aristotle, On Generation and Corruption 1.5, 320a8–321b33; cf. Aquinas, Commentary on Aristotle’s On Generation and Corruption, bk. 1, lect. 11–17.) but still more has to be said about it in the book On the Generation of Animals, to which the consideration of food of animals pertains. (Gauthier, p. 56, states that no such passage is found in On the Generation of Animals, and that Aristotle at 442a3 may have had in mind a treatise On Nourishment that he never wrote.) But now, as far as pertains to the present proposal, one point must be touched on, namely that natural heat actively augments by an expansion, and prepares nourishment by digesting, inasmuch as it draws out what is light and sweet and leaves what is salty and bitter because of its heaviness, which is why all feces of animals are quite bitter or salty. He illustrates this by something similar in the universe as a whole. What natural heat does in animals and plants, the sun’s heat does in external bodies: it draws out the fine moistness and leaves what is earthen and dense. Hence rainwater is sweet, although the sea, from which most evaporation occurs, is salty. From this he concludes that all things are nourished by sweetness, which is drawn out by natural heat.

147. Then when he says but other flavors (442a8), he gives the cause of the admixture of other flavors into food. He says that other flavors are mixed in sweet food, which alone nourishes, for seasoning, as is evident with the spicy and sharp flavor, so that they may restrain the sweetness from nourishing excessively. For sweetness is extremely filling, and floating, for it is easily drawn out by heat because of its lightness.