In philosophy, reality is the state of things as they
actually exist, rather than as they may appear or might be imagined. In a wider
definition, reality includes everything that is and has been, whether or not it
is observable or comprehensible. A still more broad definition includes
everything that has existed, exists, or will exist. Philosophers,
mathematicians, and other ancient and modern thinkers, such as Aristotle,
Plato, Frege, Wittgenstein, and Russell, have made a distinction between thought
corresponding to reality, coherent abstractions, and that which cannot even be
rationally thought. By contrast existence is often restricted solely to that
which has physical existence or has a direct basis in it in the way that
thoughts do in the brain. Reality is often contrasted with what is imaginary,
delusional, in the mind, dreams, what is abstract, what is false, or what is
fictional. The truth refers to what is real, while falsity refers to what is
not. Fictions are considered not real.
