Infallibility refers to an inability to be wrong. It can be applied within a specific domain, or it can be used as a more general adjective. The term has significance in both epistemology and theology, and its meaning and significance in both fields is the subject of continued debate.
Infallibilism
Epistemology, a branch of philosophy, is concerned with the question of what, if anything, humans can know. The answer to the issue of whether or not a human can be infallible depends on the philosophical school.
Advocates of philosophical skepticism claim that one cannot know anything with certainty, much less be infallible.
Infallibilists hold that knowledge requires absolute certainty, in the sense that if one knows that something is true, it is impossible that it could have turned out to be false.
Advocates of subjectivism claim that there is no objective reality or truth, and therefore anyone can be considered infallible, since whatever is within a person's consciousness is considered the real and the true.
Advocates of reason and rationality claim that one can gain certainty of knowledge, through a process of extreme refinement measures unlikely to be perfected enough for someone to assurably say "certainty of this knowledge is absolute", yet also assume by chance that one could land on the objective without the knowledge being confidently described as "universally certain", thus as a result, advocates tend to avoid this altogether and instead rely upon Occam's Razor as a suitable means for obtaining knowledge.
Biblical infallibilityBiblical inerrancyInfallibility of the Church and Papal infallibility
The Oxford Dictionary of the Christian Church defines infallibility as "Inability to err in teaching revealed truth". Catholic and Eastern Orthodox theology claim that the Church is infallible, but disagree as to where infallibility exists, whether in doctrines, scripture, or church authorities.
In Catholic theology, Jesus, who is the Truth, is infallible, but only a special act of teaching by the church's bishops may properly be called "infallible".