Flora Unveiled

From Empedocles to Theophrastus j 213

213 213

Whenever one body part saw another it fell in love with it, and the parts would mate

and become fused. After repeated couplings, various random combinations arose, but only

the most successful survived, as when arms and legs came together with a body. Humans

came into existence when all the necessary body parts came together, although some com-

binations were less successful than others. Among the earliest humans were ox- headed

“androids,” half man and half woman, which later had to be separated because of strife.

Aristotle and many other later Greek philosophers viewed Empedocles’s evolutionary

theory with considerable skepticism. Aristotle was firmly committed to a static, unchang-

ing universe, in which all of earth’s species were created intact at the beginning, each with

its particular degree of perfection that determined its proper place in Nature’s hierarchy.

Aristotle dismissed the attempts of the pre- Socratic philosophers to develop an evolution-

ary scheme for the origin of species. For example, he mocked Empedocles for failing to apply

his evolutionary scheme for animals based on the random assembly of body parts to plants:

So, did there come into being in plants “ ‘vine- like [plants] with olive faces,”‘ like the

“ ‘oxlike [animals] with men’s faces,”‘ or not? For it is absurd. But they should have, if

it also happened in animals.^7

A clue to Empedocles’s ideas about reproduction in plants can be found in an oft- cited

fragment in which he likens the production of fruit by olive trees to the laying of eggs by

birds: “so first tall trees lay olive eggs.”^8

According to an interpretation attributed to the Roman author Aëtius, the quotation

refers to Empedocles’s belief that trees were the first living beings to appear on earth and

that the olive was the first tree. Trees (and presumably other plants) sprouted from the earth

intact before the evolution of animals. The cosmos was still in an undifferentiated state,

and the two sexes had not yet been separated. Thus, trees contained both male and female

principles:

Trees first of living beings sprang from the earth, before the sun was unfolded in the

heavens and before day and night were separated; and by reason of the symmetry of

their mixture they contain the principle of male and female.^9

As we shall see, although Aristotle rejected Empedocles’s theory of animal evolution,

he adopted Empedocles’s idea that plants, unlike animals, are not differentiated into sexes.

Hippocrates and the “Four Humors”

Hippocrates was among the first to apply the new materialistic approach of the pre- Socratic

philosophers to the practice of medicine. He was born on the Greek island of Kos off the

southern coast of Asia Minor, and it was there, under a large oriental plane tree, that he estab-

lished his famous medical school.^10 Hippocrates believed that all remedies should be firmly

grounded on direct experience rather than folklore, and he made no reference to supernatu-

ral causes of illness— a clear break with traditional practices. He is also the source of the idea,

popular during the Middle Ages, that disease is the result of imbalances of four fluids, termed

humors: blood, phlegm, yellow bile, and black bile.^11 Hippocrates integrated the four humors