Though not a long-held widespread belief, the idea of evolution has echoed through human history. Intertwined with the concept of evolution was the issue of how life itself came about.
Ancient Indian Vedic texts, dating 3,000 years ago or even earlier, blithely considered life as a fact: particles of life pervade the universe, taking form when conditions allow.
In the 6th century bce, Greek philosopher Thales of Miletus declared that the world started from water, as did life. A century later, Greek philosopher Empedocles asserted several insights that had lasting impact. One was that all things were of 4 primal elements: air, fire, earth, and water.
In a seminal variant of the conservation of energy, Empedocles believed that no new matter was ever created. Only its form changed, as an admixture of the 4 elements. Empedocles also formulated theories of inheritance and evolution to explain adaptation to habitat.
Ancient Greek philosophers Plato and Aristotle had their own abstractions about the nature of things. Plato was an idealist. Everything in Nature derived from nonmaterial eternal ideas (“forms”).
Aristotle one-upped that by bifurcation, embracing dualism. The material world exists, but material living beings are also suffused with a vital principle – entelechy – that conducts the processes of organisms. Entelechy is nonmaterial, and therefore undiscoverable by scientific investigation.
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Though reared in poverty, Al-Jahiz thirsted for knowledge. He moved to Baghdad as a young man and became one of the greatest, and most prolific, Arab scholars of all time. In his encyclopedic Book of Animals (~860), Al-Jahiz wrote:
Animals engage in a struggle for existence: for resources, to avoid being eaten and to breed. Environmental factors influence organisms to develop new characteristics to ensure survival, thus transforming into new species. Animals that survive to breed can pass on their successful characteristics to offspring.
Persian polymath Nasīr al-Dīn Tūsī wrote Akhlaq-i-Naseri (1232), a treatise on ethics which proposed a hierarchy of life that was accepted by other natural philosophers and remains a falsity that still rings true with many, including many biologists who should know better.
Animals are higher than plants, because they are able to move consciously, go after food, find and eat useful things. There are many differences between the animal and plant species. The animal kingdom is more complicated.
Reason is the most beneficial feature of animals. Owing to reason, they can learn new things and adopt new, non-inherent abilities. The first steps of human perfection begin from here.
The human has features that distinguish him from other creatures, but he has other features that unite him with the animal world, vegetable kingdom or even with the inanimate bodies. Before humans, all differences between organisms were of the natural origin. The next step will be associated with spiritual perfection, will, observation, and knowledge.
All these facts prove that the human being is placed on the middle step of the evolutionary stairway. According to his inherent nature, the human is related to the lower beings, and only with the help of his will can he reach the higher development level. ~ Nasīr al-Dīn Tūsī
An evolutionary hypothesis underlay this hierarchical scheme.
The organisms that can gain the new features faster are more variable. As a result, they gain advantages over other creatures. The bodies are changing as a result of internal and external interactions. ~ Nasīr al-Dīn Tūsī