(note: this is an attempt to explain set of assumptions that are rarely made explicit or analysed. The purpose of this short piece is to explain, as clearly as possible, what I call justificationism. I am interested in receiving feedback regarding anything part which is unclear and needs improvement. Thank you.)
Justificationism is the presupposition that knowledge must be certified, verified, validated, confirmed or in some other way justified. In other words, if a belief is knowledge then it is in some way justified, and if a belief is unjustified then it is not knowledge. It follows that any claim to knowledge can be criticised by asking for its justification, and failure to provide sufficient justification is enough to reject that claim to knowledge. in this context, a rational belief is one which is justified, and a rational person is one who provides evidence, good reasons or proof to justify what he believes.
For a justificationist, the purpose of philosophical investigation is not a search for true belief, but a search for justified belief. This difference is subtle but important: while a justified belief is always true, an unjustified belief is not necessarily false. The justificationist's focus is upon the subjective justifiability of beliefs, and not the objective truth-value of propositions. For example, a justificationist is not concerned with whether the proposition 'this table is white' is true, but whether the belief 'this table is white' is justified. In other words, belief in a true proposition is not knowledge, only justified belief in a true proposition is knowledge.
To determine if a claim to knowledge is a justified belief, a justificationist asks that evidence, good reasons, or proof be provided as justification, and failure to provide sufficient justification is enough to reject that claim to knowledge. It follows that to obtain knowledge it is necessary to identify an authority or authorities which are sufficient to justify beliefs, otherwise there could be no justified belief. For example, to justify beliefs a justificationist might appeal to the authority of sense experience, intellectual intuition, the Pope, the Qu'ran, etc. in this context, philosophical investigation involves examining competing beliefs to see if they are reducible to, or derivable from, a preferred authority.
If a justificationist concludes that no authority is sufficient to justify any belief whatever, then all claims to knowledge are unjustified. It follows that there is no way to choose between competing claims to knowledge, because to such a justificationist every belief is equally unjustified, and therefore equally justified. In this context, philosophical investigation concerns the interpretation of society, ideas, philosophers and texts; everything is relative and such notions as truth, reality and morality are reduced to social constructs, collective fictions, myths and stories.
These two types of justificationism can be described as authoritarianism and anarchism, where the former adopts an authority, such as sense experience, intellectual intuition, the pope, the Qu'ran, etc. and the latter rejects all authority whatever. The authoritarian tradition is represented by the majority of western philosophy, such as empiricism, objectivism, logical postivism, foundationism, Christianism, Islamism, etc. whereas the anarchistic tradition is represented by scepticism, postmodernism, relativism, deconstructionism, nihilism, etc. it is important to understand: whatever differences may appear between authoritarian and anarchistic philosophers, and however much they disagree, both sponsor justificationism.
Western philosophical tradition is dominated by justificationist philosophies and philosophers, to such an extent that few recgonise that they are justificationists, or that there may be an alternative. the presuppositions of justificationism are implicit in almost all philosophical discussion, and uncritically accepted. These presuppositions constitute a reinforced dogmatism, because justificationism defines the rules by which competing proposals are evaluated, it can ensure its own protection from competitors, and any attempt to introduce an alternative can be dismissed as unjustified.