Origin of plant science
Aristotle, who was Theophrastus’s mentor at the Lyceum in ancient Athens, complained bitterly at the way human attention is invariably focused on self-interest and what can be exploited in the world, rather than trying to understand and explain what is going on. He objected:
‘How tiresome it is to keep asking of natural things – what is its use? . . . Once we have got what we need to survive, we should turn our attention to understanding nature in terms of its own ends and goods‘.
Biology was born when Aristotle and Theophrastus divided up the living world into animals and plants with Aristotle beginning a systematic account of the former and Theophrastus the latter. Plant science began with Theophrastus who, at the very outset of his Enquiry into Plants, responded to Aristotle’s request for an impartial investigation of the natural world by issuing a challenge to future plant scientists:
We must consider the distinctive characters and the general nature of plants from the point of view of their morphology, their behaviour under external conditions, their mode of generation and the whole course of their life
To satisfy his curiosity about plants Theophrastus used objective reason, what might be called analytic empiricism (see Socrates, Plato & Aristotle and Reason & science) a much more rigorous methodology than the proto-botany of the ancient civilizations of Egypt and the Mediterranean, Mesopotamia, India, and China all of which emphasised the various ways of using plants, the learned or priestly members of society having particular interest in the medicinal properties of plants. Theophrastus looked beyond plant utility to ask additional questions about the plants themselves – about their structure and function – how they were related to one-another in form, how they reproduced, their physiology, ecology, geography and so on. His studies were part of a research program in an institute of learning, the Lyceum in Athens, which along with the Academy of Plato served as models for today’s universities. Like his mentors Theophrastus questioned everything he was told, always demanding evidence and clear thinking: he was therefore suspicious of the views of his day, the prevailing myths, the influence of deities, and all manner of questionable subjective beliefs and traditions. He was in the tradition of thinkers like Empedocles (c. 495–435 BCE) who had not only derived a crude theory of evolution but also suggested that there was sex in plants, both theories well ahead of his time. Theophrastus’s challenge does not sound unduly onerous to us today but historically it proved extraordinarily difficult to carry out as amply demonstrated by the fact that it took 1500 years for the flame of plant science to be reignited as plant study was reduced once again to descriptive pharmacology. Rather than being a new beginning, Theophrastus’s botany was more a botanical culmination of Ionian Presocratic philosophy.
The ancient Greeks had discovered a method of penetrating and understanding the natural world as never before, a highly effective method that we still cherish today. What they had discovered was science, and it would transform the world. Science was not a miracle technology or secret recipe – it was a mode of thinking.
So how did the history of plant science unfold after Theophrastus?
The history of botany has been the topic of several books but this account has drawn heavily on the excellent History of Botanical Science by Alan Morton (1981), it is discussed mainly from a Western perspective.
Economic botany, plant introduction, gardens & plant science
Other developments at this time included the curious, beautiful and economically useful plant trophies sent back to Athens by explorers and from military campaigns. Epicurus had established what was possibly the first decorative garden in Athens and gardens were generally becoming more elaborate and commonplace across the Mediterranean and Persian world descending, we assume, from the ancient palace gardens and designed city precincts of ancient Egypt and Mesopotamia. But the best known medicinal manuscript influenced by this period of history was written in about 65 CE was De Materia Medica (Materials of Medicine) a list of herbs and their properties written by Pedanios Dioscorides (c. 40–90 CE) a Greek physician in the Roman army. For many centuries this work would be regarded as definitive and slavishly copied again and again well into the Renaissance even though we now know of works like De Simplicibus by the brilliant Greek physician in Roman Pergamon, Galen (c.131–201 CE) which is much more informative.