Platonism, a philosophical movement dating back to Plato, who had already talked about intuition supporting its superiority over reasoning, affirmed the existence of a higher truth: the ideas, of the eternal ideal forms, immutable, and incorruptible, from which originates the sensible world, which we perceive, subject to becoming, corruption, and death. Platonism is associated with Enlightenment of the eighteenth century, considered having left the state of intellectual minority, becoming older on a rational level and learning to think for themselves, clearly breaking away from superstition. The warning of Kant is [....] “Have the courage to use your own intelligence!” This is the motto of' Enlightenment.

Platonism is opposed by empiricism, a very complex term that designates the philosophical movement, born in the second half of the seventeenth century in England, whereby human knowledge is derived exclusively from the senses or experience. The Anglo-Saxon greatest exponents of empiricism were John Locke, George Berkeley, and David Hume: they denied that humans have innate ideas or that anything was knowable regardless of experience.

Empiricism as philosophical current opposed ‘innatism 'and' rationalism ', which have knowledge derived through deduction from rational principles, obvious a priori.

The theory of anamnesis (or recollection) of Plato can be considered among the first and most well-known examples of innatism of Western philosophy. Regaining possession of Orphic and Pythagorean tradition, Plato made it the core of its doctrine of knowledge. The existence of innatism, according to Plato, was demonstrated by the fact that our knowledge of the material world are based on mathematical models and forms that are not reflected in it, but they seem to come from a place called iperuranium where our intellect had contemplated them before born. According to Plato, memory is carried out in an immediate and intuitive form, by sudden flashes, but must be stimulated by sense perception, which thus plays an important role, as it offers the intellect the opportunity to start reminiscence.

The linguistic analyses of the Noam Chomsky’ school have indicated the probable existence of innate grammatical structures, that are present in the brain at birth (e.g. in Broca's area), through which children acquire one (or more) languages with more speed than would be possible without these innate structures (theory of universal grammar).

More recently, in developmental psychology, mention is made of modular innatism, assuming the basic idea that the mind is made up of sets more or less related to structures or innate modules, encapsulated, specialized and selected by evolution to perform particular functions.

For Descartes the existence of an infinite and perfect God is revealed in the presence of innate ideas, as he can not arise either from adventitious ideas (which have in them the limitations of finite nature) nor by artificial ideas (which are invented by man, imperfect and finite by nature). The definition of God as a most perfect being, eternal and immutable means you can not own a concept produced by instability and human imperfection. What makes an idea that has in itself the concept of perfection must necessarily be perfect.

The conception of the ‘idea’ is central to the philosophy of Hegel. Even in Schopenhauer the ideas, first stage of the objectification of the will, are considered forms and universal models.

Among the philosophers who have spoken out against forms of innatism there is John Locke, who anticipating one of the fundamental themes of the Enlightenment claimed that the human mind at birth is a ‘tabula rasa’ on which only experience would write knowledge and ideas.

Locke wondered why in his time this view of innatism was still so widespread and responded by saying that the end of innatists would be to subtract some principles to the continuous assessment of the experience in order to present themselves as guardians interested in absolute truths.

Radicalizing the position of Locke, David Hume urged to "throw in the fire" any written philosophical material that presumed to pivot on an innate knowledge; and recognizing as valid only what is learned from the experience, he ended up destroying those concepts of causality, objectivity, universality, substance considered arbitrary. Kant, while recognizing himself as a debtor of Hume for having awakened him from the "dogmatic slumber" of metaphysics, saw thereby endangered the very foundations of science, and therefore restored, through its Copernican revolution, the principle of objectivity within that of subjectivity, albeit on a formal level that shortly thereafter, with the idealism, would also become substantial.

Innatism continues to be revived today as part of anthropology about the study of Claude Levi-Strauss concerning structures of taboos and myths.

Psychological innatist views judging of major importance  the inherited elements in understanding the origin and structure of human behavior, are present in the theory of the specific instincts by W. Mac Dougall, in the typology of W. Shelton and in the ethology of Konrad Lorenz.

More recently, in developmental psychology, entered the concept of ‘modular innatism', taking the basic idea that the mind is made up of sets more or less related to structures or innate modules, specialized and selected by evolution to perform particular functions

Today the meaning of the term ‘idea’ has been gradually downsized to a psychological connotation, which reduces it to a simple content of the mind.

According to some definitions already seen about empiricism, the idea is understood as a representation that the mind would compose for the recognition of the elements learned from experience, and the combination of which would stand beside the processing function design. In particular, according to Konrad Lorenz, ideas would be divorced from a content of truth, being conceived only as the product of our mental categories phylogenetically derived from the evolution of the species, and therefore proved useful to life.