Pierre A. Riffard is a French philosopher and specialist in esotericism. Born in Toulouse (France), he is a professor of pedagogy and philosophy at the University of the French West Indies and Guiana (Université des Antilles et de la Guyane).
Teaching in the French overseas departments and territories and elsewhere: Asia, Oceania, Sub-Saharan Africa, Guiana.
 For Pierre A. Riffard, esotericism is "occult teaching, doctrine or theory, technique or process, of symbolic expression, of a metaphysical nature, of initiatory intent. Druidism, compagnonnage (the traditional French system of training craftsmen), alchemy are esotericisms."
 Pierre A. Riffard defended a Doctor of Philosophy thesis on the Greek formula ἓν καὶ πᾶν (hen kai pān, "the One and the All"), then a Doctor of Arts thesis on L'Idée d'ésotérisme [The Idea of Esotericism] (Paris 1 Sorbonne University, 1987), after conducting research into occultism.
Author of the Dictionnaire de l'ésotérisme [Dictionary of Esotericism] (Payot, 1983), which is an authoritative work in the field, he has also written two sizeable volumes for the "Bouquins" collection of France's Editions Robert Laffont publishing house; one is devoted to esotericism in general: L'ésotérisme. Qu'est-ce que l'ésotérisme ? [Esotericism. What is Esotericism?], 1990; the other treats with non-Western esotericisms: Ésotérismes d'ailleurs [Esotericisms from other lands], 1997. As soon as 87, he proposed nine invariants for defining an esotericism:
 In other terms, 
 As regards form, esotericists have a secret: paralipsis (apophasis). They purport to say nothing, while at the same time discreetly revealing something (In saying "I will say nothing about the sacred nature of sexuality", I have said that sexuality does indeed have a sacred nature). For example, symbols such as the apple or the coiled serpent reveal numerous clues or keys to sexuality, while simultaneously appearing to obfuscate the discourse or image.
 As regards content, esotericists have another secret: reversion. They reverse ordinary ideas, they turn around commonplace behaviour, they overturn shared emotions, to return to the original. For example, kundalini yoga sends sexual energy up to the brain, and the alchemist returns to primary matter, when everything becomes possible and powerful again.
 As regards sense, esotericists have no secrets; they just adopt a lifestyle, one which gives priority to the interior of things. For example, in love they prefer a state of consciousness higher than sexual pleasure; in alchemy they are more interested in the solar image of gold than its market value.
"Riffard's approach may thus be characterized as universalist, religionistic, and trans-historical: Esotericism is a basic 'anthropological structure' and as such not dependent on cultural mediation. Its scope in time and space includes the whole of human history." -Wouter J. Hanegraaff. 
 Pierre A. Riffard recently published essays examining the lifestyle of philosophers from a psychological and sociological point of view (Les philosophes: vie intime ["Philosophers: private life"], 2004; Philosophie matin, midi et soir ["Philosophy morning, noon and night"], 2006. Paris: Presses Universitaires de France). In Les philosophes: vie intime, he draws attention to some of the philosopher's human traits, which are not generally mentioned, covering everyone from Thales to Sartre:
 "Pierre Riffard's vision of philosophy is that of a being torn between opposing demands: analysis and synthesis, the singular and the universal, certainty and doubt." ("La vision qu'a Pierre Riffard du philosophe est celle d'un être tiraillé par des sollicitations contraires : analyse et synthèse, le singulier et l'universel, certitude et doute.") -Thomas Régnier.
 Thanatology is the study of death among human beings.
 Raising the issue of the afterlife is no plain matter, something like “I believe in Paradise”. It actually is a speculative strategy, a rational reckoning, combining several concepts and requiring a number of successive choices. It looks like a decision tree!
 As for the afterlife itself, several problems arise. First of all, problems of method.
 1 – Is it possible to ascertain whether there is an afterlife (or life after death) : yes (1a), maybe (1b), no (1c) ?
 2 – Where is documentation to be found?
 3 – What is to be considered as suitable evidence?
 Next come the philosophical queries.
 A - Should one negate (A1) or assert (A2) or suspend one’s opinion (A3) on the afterlife ?
 B – Who survives : a single individual (B1), an elite (B2), a community (B3), Humanity (B4), the World (B5) ?
 C - What survives : the soul (C1), a soul, the mind, the Self... ?
 D- Under what shape : some specific element in the individual, some universal element... ?
 E – Since when : the death of the individual, Doomsday... ?
 F – Over what span of time : eternity ?
 G – What type of time : cyclical, over an evolutionary period... ?
 H – Where : a subterranean place, Heaven... ?
 I – Following which law : God’s Will, Chance, One’s karma... ?
 J – What types of survival : reincarnation, resurrection... ?
 K – to what ultimate end : fusing into God, dissolution of the Self... ?
 The Christian view of life after death is a combination of assertions : "the afterlife is a fact"(A2), humanity is concerned (B4), spiritualism (C1), Doomsday (E2)... and resurrection
Skepticism and scientism bring reflection to an abrupt ending through the suspension of judgment (A3), it agrees with Wilder Penfield’s words : "Whether energy can come to the mind of man from an outside source after his death is for each individual to decide for himself. Science has no such answer" (The Mystery of the Mind, 1976).
 All things considered, about a dozen ascertained types of survival are possible; they may either co-exist or follow one another and may vary according to the individuals, the souls, the actions. The history of religions mainly highlights a few types : neutral form of life (ex : the limbo in the Roman Catholic faith), shadow existence (Homer and the Ancient Jews), demonic life, damnation or salvation, migration of the souls through metempsychosis (whether the soul takes the shape of an animal or a plant or a human being) or reincarnation (in the human body's shape), catasterisation (transfer of the souls to the stars), palingenesis (one does not die but undergoes some transformation, just like mould turning into fungi), eternal return (all souls living through the same experiences again, thousands of years later, through cosmic palingenesis).