On his return from Puerto Rico in 1970, he created the Institute of Applied Biology (IBA). From then on, whilst continuing his experimental work -at that time in the food industry- Cordón set out to systematize his previous work and started to write the Evolutionist Treatise on Biology. A Natural History of the Action and Experience of Living Beings.
At the Institute of Applied Biology (IBA). Madrid, 1974
Cordón considered that this treatise met the objective need of current biology to systematically order the enormous stock of empirical and experimental data so that each type of current living being (with all its anatomical, physiological and behavioural particularities, etc.) could be interpreted intelligibly. It did so based on the assumptions that this living being has a specific experience, that it emerges from an internally coherent soma, that it has an explainable interaction with its environment, and that it originated in a specific stage of biological evolution.
”It is a treatise that refers to living beings without setting out to classify them and describe them, as an empirical treatise of biology would do, and without making an ordered compendium of how living beings of the different types respond to human actions aimed at clarifying structural or functional particularities of various types, as an experimental treatise of biology would do. An evolutionist treatise of biology deals with a higher order of problems, or perhaps a subsequent one: firstly, it attempts to account for the empirical and experimental knowledge that man has acquired on living beings, mainly in the last two and a half centuries; secondly, it attempts to understand why they are they way they are -especially their essential characteristic as living beings- and the causes of their similarities and differences, through research into how they could have originated and become differentiated in terms of the particular framework that has been established for each one by the gradual change in the earth's biosphere”.
Cordón divided the Treatise into three parts, dedicated to the living beings of each of the three levels: Part One, on the origin, nature and evolution of the protein and its associations; Part Two, on the origin, nature and evolution of the cell and its associations; and Part Three, on the origin, nature and evolution of the animal.