Peter Klein

There are many things that could be wrong with foundationalism. For example, some have claimed that a so‐called basic belief cannot be both 1) a reason for non‐basic beliefs and 2) such that it cannot be provided with at least prima facie justification.1 If something is a reason, they say, then that something has to be a proposition (or sufficiently proposition‐like) and if it is a proposition (or sufficiently proposition‐like), then it is the kind of thing that requires a reason in order to be even prima facie justified.2 Another reason that some give for rejecting normative foundationalism is that it leads directly to skepticism.3 There is no way, they claim, to move from so‐called basic propositions (typically given as first person introspective reports) to “external world” propositions by employing normatively acceptable principles of reasoning.4 Still others have thought that the invention of a nonrea‐soned reason was as ad hoc as the invention of an unmoved mover.5.

As the Pyrrhonians made clear, reasons that adequately justify beliefs can have only three possible structures: foundationalism, coherentism, and infinitism. Infinitism—the view that adequate reasons for our beliefs are infinite and non-repeating—has never been developed carefully, much less advocated. In this paper, I will argue that only infinitism can satisfy two intuitively plausible constraints on good reasoning: the avoidance of circular reasoning and the avoidance of arbitrariness. Further, I will argue that infinitism requires serious, but salutary, revisions in our evaluation of the power of reasoning. Thus, reasoning can not provide a basis for assenting to a proposition—where to assent to a proposition, p, means to believe that we know that p. A non-dogmatic form of provisional justification will be sketched. Finally, the best objections to infinitism, including those posed by the Pyrrhonians, will be shown (at least provisionally!) to be inadequate.

Philosophers have sought to characterize a type of knowledge — what I call real knowledge — which is significantly different from the ordinary concept of knowledge. The concept of knowledge as true, justified belief — what I call knowledge simpliciter — failed to depict the sought after real knowledge because the necessary and jointly sufficient conditions of knowledge simpliciter can be felicitously but accidentally fulfilled. Real knowledge is knowledge simpliciter plus a set of requirements which guarantee that the truth, belief and justification conditions are not accidentally conjoined. Two of those requirements have received considerable attention in recent literature by the defeasibility theorists and the causal theorists. I argue that a third requirement is needed to block the merely coincidental cosatisfaction of the belief and justification conditions and to capture our intuitions about the epistemic agent who possesses real knowledge. That condition ascribes a disposition to the real knower to believe all and only justified propositions in virtue of his/her belief that the propositions are justified. Two consequences of that requirement are discussed: (1) if S really knows that p, then S knows simpliciter that S knows simpliciter that p and (2) the iterative feature of real knowledge mentioned in (1) provides a basis for the rejection of a particularly pernicious form of scepticism.

O propósito deste artigo é mostrar como podem ser desenvolvidas explicações robustas de justificação e de certeza no interior do infinitismo. Primeiro, eu explico como a concepção infinitista de justificação epistêmica difere das concepções fundacionista e coerentista. Em segundo lugar, explico como o infinitista pode oferecer uma solução ao problema do regresso epistêmico. Em terceiro lugar, explico como o infinitismo, per se, é compatível com as teorias daqueles que sustentam 1) que o conhecimento requer certeza e que uma tal forma superior de conhecimento é possível, bem como com as daqueles que rejeitam algum ou ambos os conjuntos em 1). Em outras palavras, o infinitismo nem endossa, nem rejeita o ceticismo, tomando-se essa tese como sendo aquela segundo a qual nós não possuímos conhecimento naquelas situações que nos parecem cognoscíveis. PALAVRAS-CHAVE – Certeza. Coerentismo. Fundacionismo. Infinitismo. Pirronismo. Regresso epistêmico. ABSTRACT The purpose of the paper is to show how robust accounts of justification and certainty can be developed within infinitism. First, I explain how the infinitist conception of epistemic justification differs from both the foundationalist and coherentist conceptions. Second, I explain how the infinitist can provide a solution to the epistemic regress problem. Third, I explain how infinitism, per se, is compatible with both the views of those who hold 1) that knowledge requires certainty and that such high-grade knowledge is possible as well as those who deny either or both conjuncts in 1). In other words, infinitism neither endorses nor rejects skepticism, taking that view to mean that we do not have knowledge in those areas commonly thought to be within our ken. KEY WORDS – Certainty. Coherentism. Foundationalism. Infinitism. Pyrrhonism. Epistemic regress

I will argue for two main points. First, the regress imbedded in infinitism need not be subject to the Structural Objection; and second, the Structural Objection does not pose a real problem for any regress. I will not be arguing for the correctness of my proposal directly. That is, as will become apparent soon, my proposal rests on two principles of reasoning which together entail infinitism and I will not present my arguments for those principles here. The purpose of this paper is to show that the objections raised by Gillett do not pose a grave problem for infinitism.

Infinitism, along with foundationalism and coherentism, is a logically possible solution to the epistemic regress problem. But unlike the other two views, infinitism has only been developed and defended as a plausible solution since the late 1990’s. Infinitists grant that although there is an ending point of any actual chain of cited reasons for a belief, no belief (including the last one cited) is fully justified until a reason for it is provided. In addition to differing with foundationalism about the existence of so-called basic beliefs, infinitism depicts reasoning as a process through which full doxastic justification is generated, rather than as a device for merely transferring doxastic justification from one belief to another. Thus, like coherentism, infinitism attempts to account for the origin of epistemic doxastic justification without invoking self-justified beliefs whose justification is transmitted through reasoning. But infinitism parts company with coherentism by maintaining (1) that circular reasoning is unable to provide a doxastic justification for any belief and (2) that there is a linear epistemic structure of our beliefs that reflects the fact that some beliefs are epistemically prior to others.