Philosophical Psychiatry

Skepticism: "...a questioning attitude or doubt toward knowledge claims that are seen as mere belief or dogma."

Skeptic: "...a person inclined to question or doubt accepted opinions."

Jon Lee is a clinical assistant professor of psychiatry at the Stanford Department of Psychiatry and Behavioral Sciences (Depression Clinic), where he founded the "Am I Good? Examining life through the lenses of Philosophical Skepticism, Moral Philosophy, and Existentialism" philosophical psychotherapy group.

Jon Lee uses an approach that consists of the use of both psychopharmacological and individual/group psychotherapeutic interventions to address depression, dissatisfaction, and unhappiness. Referred to by some as philosophical psychiatry, philosophical therapy, philosophical counseling, or philosophical psychology, Jon's approach to therapy/counseling begins with the building of one's worldview / lens from a first principles perspective by asking the fundamental questions posed by philosophers and scientists spanning philosophical / intellectual traditions across time, including: 

Questions include 'how do we know what we know?', 'what is the meaning of life?', 'what is the purpose of life?', 'does God exist?', 'what matters?', 'what is value?', 'what is good?', 'do we have moral obligations?', 'what are our moral obligations?', 'do we have rights?', 'what are rights?', 'do we have free will?', etc. 

Jon Lee's approach draws heavily from the philosophical works of Epicurus, Baruch Spinoza, David Hume, Friedrich Nietzsche, Ludwig Wittgenstein, Arthur Schopenhauer, Albert Camus, Jean-Paul Sartre, John Rawles, etc.

A crowdsourced primer on skepticism: 

Skepticism, also spelled scepticism, is a questioning attitude or doubt toward knowledge claims that are seen as mere belief or dogma.[1][2] For example, if a person is skeptical about claims made by their government about an ongoing war then the person doubts that these claims are accurate. In such cases, skeptics normally recommend not disbelief but suspension of belief, i.e. maintaining a neutral attitude that neither affirms nor denies the claim. This attitude is often motivated by the impression that the available evidence is insufficient to support the claim. Formally, skepticism is a topic of interest in philosophy, particularly epistemology. More informally, skepticism as an expression of questioning or doubt can be applied to any topic, such as politics, religion, or pseudoscience. It is often applied within restricted domains, such as morality (moral skepticism), atheism (skepticism about the existence of God), or the supernatural.[3] Some theorists distinguish "good" or moderate skepticism, which seeks strong evidence before accepting a position, from "bad" or radical skepticism, which wants to suspend judgment indefinitely.

Philosophical skepticism is one important form of skepticism. It rejects knowledge claims that seem certain from the perspective of common sense. Radical forms of philosophical skepticism deny that "knowledge or rational belief is possible and urge us to suspend judgment on many or all controversial matters." More moderate forms claim only that nothing can be known with certainty, or that we can know little or nothing about nonempirical matters, such as whether God exists, whether human beings have free will, or whether there is an afterlife. In ancient philosophy, skepticism was understood as a way of life associated with inner peace.

Skepticism has been responsible for many important developments in science and philosophy. It has also inspired several contemporary social movements. Religious skepticism advocates for doubt concerning basic religious principles, such as immortality, providence, and revelation.[4] Scientific skepticism advocates for testing beliefs for reliability, by subjecting them to systematic investigation using the scientific method, to discover empirical evidence for them.

Moral skepticism (or moral scepticism in British English) is a class of meta-ethical theories all members of which entail that no one has any moral knowledge. Many moral skeptics also make the stronger, modal claim that moral knowledge is impossible. Moral skepticism is particularly opposed to moral realism: the view that there are knowable and objective moral truths.

Moral skepticism is divided into three subclasses: moral error theory (or moral nihilism), epistemological moral skepticism, and noncognitivism.[1] All three of these theories reach the same conclusions, which are:

(a) we are never justified in believing that moral claims (claims of the form "state of affairs x is (morally) good," "action y is morally obligatory," etc.) are true, and, furthermore,

(b) we never know that any moral claim is true.

However, each method arrives at (a) and (b) by a different route.

Moral error theory holds that we do not know that any moral claim is true because

(i) all moral claims are false,

(ii) we have reason to believe that all moral claims are false, and

(iii) since we are not justified in believing any claim we have reason to deny, we are not justified in believing any moral claims.

Epistemological moral skepticism is a subclass of theory, the members of which include Pyrrhonian moral skepticism and dogmatic moral skepticism. All members of epistemological moral skepticism share two things: first, they acknowledge that we are unjustified in believing any moral claim, and second, they are agnostic on whether (i) is true (i.e. on whether all moral claims are false).

Pyrrhonian moral skepticism holds that the reason we are unjustified in believing any moral claim is that it is irrational for us to believe either that any moral claim is true or that any moral claim is false. Thus, in addition to being agnostic on whether (i) is true, Pyrrhonian moral skepticism denies (ii).

Dogmatic moral skepticism, on the other hand, affirms (ii) and cites (ii)'s truth as the reason we are unjustified in believing any moral claim.

Finally, Noncognitivism holds that we can never know that any moral claim is true because moral claims are incapable of being true or false (they are not truth-apt). Instead, moral claims are imperatives (e.g. "Don't steal babies!"), expressions of emotion (e.g. "stealing babies: Boo!"), or expressions of "pro-attitudes" ("I do not believe that babies should be stolen.")

Scientific skepticism or rational skepticism (also spelled scepticism), sometimes referred to as skeptical inquiry,[1] is a position in which one questions the veracity of claims lacking empirical evidence. In practice, the term most commonly references the examination of claims and theories that appear to be beyond mainstream science, rather than the routine discussions and challenges among scientists. Scientific skepticism differs from philosophical skepticism, which questions humans' ability to claim any knowledge about the nature of the world and how they perceive it, and the similar but distinct methodological skepticism, which is a systematic process of being skeptical about (or doubting) the truth of one's beliefs.