Idea
In philosophy and in common usage, an idea is the result of thought. Also in philosophy, ideas can also be mental representational images of some object. Many philosophers have considered ideas to be a fundamental ontological category of being. The capacity to create and understand the meaning of ideas is considered to be an essential and defining feature of human beings.
An idea arises in a reflexive, spontaneous manner, even without thinking or serious reflection, for example, when we talk about the idea of a person or a place. A new or an original idea can often lead to innovation. Our actions are based upon beliefs, beliefs are patterns or organized sets of ideas.
Etymology
The word idea comes from Greek, ,, from the root of ἰδεῖν,.History
An argument over the underlying nature of ideas was opened by Plato, whose exposition of his theory of forms—which recurs and accumulates over the course of his many dialogs—appropriates and adds a new sense to the Greek word for things that are "seen" that highlights those elements of perception which are encountered without material or objective reference available to the eyes. As this argument was disseminated the word "idea" began to take on connotations that would be more familiarly associated with the term today. In the fifth book of his Republic, Plato defines philosophy as the love of this formal way of seeing.Plato advanced the theory that perceived but immaterial objects of awareness constitute a realm of deathless forms or ideas from which the material world emanates. Aristotle challenged Plato in this area, positing that the phenomenal world of ideas arises as mental composites of remembered observations. Though it is anachronistic to apply these terms to thinkers from antiquity, it clarifies the argument between Plato and Aristotle if we call Plato an idealist thinker and Aristotle an empiricist thinker.
This antagonism between empiricism and idealism generally characterizes the dynamism of the argument over the theory of ideas up to the present. This schism in theory has never been resolved to the satisfaction of thinkers from both sides of the disagreement and is represented today in the split between analytic and continental schools of philosophy. Persistent contradictions between classical physics and quantum mechanics may be pointed to as a rough analogy for the gap between the two schools of thought.
Philosophy
Plato
in Ancient Greece was one of the earliest philosophers to provide a detailed discussion of ideas and of the thinking process. Plato argued in dialogues such as the Phaedo, Symposium, Republic, and Timaeus that there is a realm of ideas or forms, which exist independently of anyone who may have thoughts on these ideas, and it is the ideas which distinguish mere opinion from knowledge, for unlike material things which are transient and liable to contrary properties, ideas are unchanging and nothing but just what they are. Consequently, Plato seems to assert forcefully that material things can only be the objects of opinion; real knowledge can only be had of unchanging ideas. Furthermore, ideas for Plato appear to serve as universals; consider the following passage from the Republic:René Descartes
often wrote of the meaning of the idea as an image or representation, often but not necessarily "in the mind", which was well known in the vernacular. Despite Descartes' invention of the non-Platonic use of the term, he at first followed this vernacular use.b In his Meditations on First Philosophy he says, "Some of my thoughts are like images of things, and it is to these alone that the name 'idea' properly belongs." He sometimes maintained that ideas were innate and uses of the term idea diverge from the original primary scholastic use. He provides multiple non-equivalent definitions of the term, uses it to refer to as many as six distinct kinds of entities, and divides ideas inconsistently into various genetic categories. For him knowledge took the form of ideas and philosophical investigation is devoted to the consideration of these entities.John Locke
's use of idea stands in striking contrast to Plato's. In his Introduction to An Essay Concerning Human Understanding, Locke defines idea as "that term which, I think, serves best to stand for whatsoever is the object of the understanding when a man thinks, I have used it to express whatever is meant by phantasm, notion, species, or whatever it is which the mind can be employed about in thinking; And I could not avoid frequently using it." He said he regarded the contribution offered in his essay as necessary to examine our own abilities and discern what objects our understandings were, or were not, fitted to deal with. In this style of ideal conception other outstanding figures followed in his footsteps — Hume and Kant in the 18th century, Arthur Schopenhauer in the 19th century, and Bertrand Russell, Ludwig Wittgenstein, and Karl Popper in the 20th century. Locke always believed in the good sense — not pushing things to extremes and while taking fully into account the plain facts of the matter. He prioritized common-sense ideas that struck him as "good-tempered, moderate, and down-to-earth."As John Locke studied humans in his work "An Essay Concerning Human Understanding" he continually referenced Descartes for ideas as he asked this fundamental question: "When we are concerned with something about which we have no certain knowledge, what rules or standards should guide how confident we allow ourselves to be that our opinions are right?" Put in another way, he inquired into how humans might verify their ideas, and considered the distinctions between different types of ideas. Locke found that an idea "can simply mean some sort of brute experience." He shows that there are "No innate principles in the mind." Thus, he concludes that "our ideas are all experienced in nature." An experience can either be a sensation or a reflection: "consider whether there are any innate ideas in the mind before any are brought in by the impression from sensation or reflection." Therefore, an idea was an experience in which the human mind apprehended something.
In a Lockean view, there are really two types of ideas: complex and simple. Simple ideas are the building blocks for more complex ideas, and "While the mind is wholly passive in the reception of simple ideas, it is very active in the building of complex ideas…" Complex ideas, therefore, can either be modes, substances, or relations.
Modes combine simpler ideas in order to convey new information. For instance, David Banach gives the example of beauty as a mode. He points to combinations of color and form as qualities constitutive of this mode. Substances, however, are distinct from modes. Substances convey the underlying formal unity of certain objects, such as dogs, cats, or tables. Relations represent the relationship between two or more ideas that contain analogous elements to one another without the implication of underlying formal unity. A painting or a piece of music, for example, can both be called 'art' without belonging to the same substance. They are related as forms of art. In this way, Locke concluded that the formal ambiguity around ideas he initially sought to clarify had been resolved.