The rhetorical device of parrhesia is derived from the classical Greek word for bombastic bluntness — saying all that must be said so that no doubt remains. Literally meaning "free speech" or "to say everything," this term refers to speaking or writing that is inherently free to scan for ultimate truth in a sea of whispered lies and conflicting stories. When the term originated at the start of the dawn of western philosophy, Greek citizens known to speak the truth were said to do so with parrhesia. They were called the parrhesiastes.
Parrhesia often refers to more than free speech, but one that is without tactful niceties. Direct, unabashed language is used in an effort to get to the heart of the listener's beliefs and change them immediately. It may be assumed that parrhesia is being rhetorically applied by a highly logical individual with moral aims, but negative parrhesia is a possibility when the speaker decides to unleash his or her thoughts in free-form, without organization and forethought. Many noted philosophers at the time, such as Plato, decried this unqualified ranting as a negative influence on effective free speech.
The opinion of the speaker of parrhesia is often immediately known, at least in general. Modern examples include religious zealots who rail against sin in bar districts, or a leader of an activist group who must immediately and passionately inform a group about his or her group's cause. Though politicians and business people often use parrhesia as a rhetorical device, it is more often to be in concert with other more tactful devices.
The concept of parrhesian speaking is primarily a classical one; the idea can be found in a range of philosophical or literary works of ancient Greece. There was the negative, more pejorative sense of the word — anyone ranting about anything in public and the more prevalent, positive style of usage. In either case, the speaker attempted to tell the truth and not sugarcoat anything.
Belief is a large part of this device. Since the speaker is attempting to assert what he or she thinks is true, opinion is inherent. Everyone listening knows that the words are the speaker's own beliefs. This style of discourse is best juxtaposed with the more evidence-based forms of truth-seeking that are credited to the Cartesian school of thought that followed the philosophy of Rene Descartes. In parrhesia, by contrast, it appears that the speaker just knows that the ground where he or she stands is solid.