Religious	conversion,	transformative	experience,	and	disagreement1 Helen	De	Cruz,	Oxford	Brookes	University,	hde-cruz@brookes.ac.uk This	is	a	draft	version	of	a	paper	that	appeared	in	Philosophia	Christi,	vol	20	(1),	265-276 1.	Religious	conversion	and	the	Independence	Principle Miguel and Catherine are both atheist philosophers and long-time friends from graduate	school.	Miguel	respects	Catherine	and	believes	she	is	his	epistemic	peer.	Both of	them	have	been	raised	in	a	liberal	environment	where	atheism	is	quite	widespread. But	they	have	also	carefully	thought	about	theism.	Neither	of	them	is	a	philosopher	of religion,	but	they	know	the	arguments	for	and	against	theism	and	they	both	agree	that the arguments against outweigh the arguments for. As a result, both are quite complacent	atheists;2	they	think	there	is	no	serious	case	to	be	made	for	theism. Miguel	meets	Catherine	at	a	philosophy	conference-it's	been	about	a	year	since they last	met.	He	has	been looking forward to seeing	his	old friend.	As they catch	up over	a	cup	of	coffee,	it	becomes	clear	that	Catherine	is	now	a	theist. "But	why?"	Miguel asks. "Didn't you think all that theist philosophy is dubious, motivated	reasoning?" "I	changed	my	mind,"	Catherine	replies. This situation	appears to	be	a case	of	peer	disagreement.	Miguel and	Catherine are	(presumably)	equally	thoughtful	in	the	domain	in	question,	and	they	have	access	to the same evidence. While their epistemic situation is not identical, they will still be similar enough to take each other to be epistemic peers, a situation that occurs frequently	in	everyday	life. Epistemologists	have	debated	whether	one	should	conciliate,	that	is,	revise	one's opinion	that	p,3	when	faced	with	a	disagreeing	peer	who	holds	that	not-p,	or	whether one	can	remain	steadfast.	One	principle	that	has	been	proposed	to	separate	these	two types	of	responses	is	the	Independence	Principle. Independence: In evaluating the epistemic credentials of another's expressed	belief	about	p,	in	order	to	determine	how	(or	whether)	to	modify 1 This research was supported by research leave funded by Oxford Brookes University. The author wishes to thank Liam Kofi Bright, Kate Kirkpatrick, Stephen Boulter, Johan De Smedt, Chad Bogosian, and Paul Copan for helpful comments to an earlier draft. 2 The phrase "complacent atheist" was coined by Feldman, and is also used by Littlejohn. See Richard Feldman, "Reasonable Religious Disagreement," in Philosophers without Gods: Meditations on Atheism and the Secular Life, ed. Louise Antony (Oxford: Oxford University Press, 2007), 194–214; Clayton Littlejohn, "Disagreement and Defeat," in Disagreement and Scepticism, ed. D.E. Machuca (London and New York: Routledge, 2013), 169–192. 3 Some conciliationists think that disagreeing parties should lower their credence that p to split the difference with their peer (See, e.g., Adam Elga, "Reflection and Disagreement," Noûs 41 (2007): 478–502). Here I will not assume that one needs to split the difference in order to be a conciliationist. my own belief about p, I should do so in a way that doesn't rely on the reasoning	behind	my	initial	belief	about	p.4 Independence delivers a plausible verdict in a variety of cases, such as Christensen's paradigmatic	mental	math	case,	where	people	disagree	about the	amount to	pay in	a restaurant	where	they	are	splitting	the	bill.5	But	the	principle	might	not	apply	to	other cases.	An	example is	elementary	math,6	where	someone	you	consider	as	an	epistemic peer	says	that	2	+	2	=	5.	This	is	no	reason	to	lower	your	confidence	that	2	+	2	=	4,	but rather,	to	revise	your	belief	that	this	person	is	an	epistemic	peer,	at	the	very	least	about elementary	mathematical facts. If someone truly believed that 2 + 2 = 5, this would demonstrate	that	this	person	is,	in	all	likelihood,	not	as	clear-headed	as	you. Would a religious conversion be more analogous to the mental math or the elementary	math	case?	Many	people	have	a	response	along	these	lines:	"I	don't	know what	happened	to	Josh.	He	was	such	a	reasonable	guy,	but	then	he	joined	Scientology.	I think	he's	gone	off the	cliff,"	or, "I	used to respect	Amy,	but	now	she is	no longer	an Evangelical Christian; I cannot respect her anymore." In such cases, people treat the conversion	as	a	situation	where	one's	epistemic	peer	has	acquired	such	an	outlandish set	of	beliefs	that	they	begin	to	doubt	the	peerhood,	akin	to	the	elementary	math	case. In	other	cases,	where	the	new	belief	is	at	least	a	live	option	(in	the	Jamesian	sense),	the case	may	appear	more	like	the	mental	math	case	(e.g.,	"I'm	not	Jewish,	but	it	does	look like	an	interesting	religion	with	a	rich	theology.	Yehuda	might	be	right,	or	I	might	be"). There	is	a	further	problem	for	treating	conversion	cases	as	peer	disagreements:	religious conversions	tend	to	be	transformative.	This	makes	it	hard	to	see	whether	the	person	is still one's epistemic peer, or	what the proper response should be. As a result of this transformation,	the	beliefs	of	a	dissenting	peer,	arising	from	a	religious	conversion,	do not	have	straightforward	evidential	value.7 2.	Conversion	as	a	transformative	experience Some	experiences	transform	us,	both in	who	we	are	and	what	we	know.	L.A.	Paul	has termed such experiences "transformative experiences."8 They are personally transformative,	in	that	they	change	who	you	are	as	a	person,	and	they	are	epistemically 4 David Christensen, "Disagreement, Question-Begging, and Epistemic Self-Criticism," Philosopher's Imprint 11 (2011): 2. 5 David Christensen, "Epistemology of Disagreement: The Good News," The Philosophical Review 116, no. 2 (2007): 187–217. 6 Jennifer Lackey, "What Should We Do When We Disagree?" in Oxford Studies in Epistemology vol. 3., ed. Tamar Gendler and John Hawthorne (Oxford: Oxford University Press, 2010), 274–293. 7 There are several definitions of epistemic peerhood, with some focusing on evidential equality, others focusing on cognitive equality, and yet others on the extent to which agents show epistemic virtues, such as thoughtfulness and thoroughness. Here, I will employ the term "epistemic peer" in a fairly loose notion to mean someone whom we consider as an epistemic peer about a given question, prior to becoming aware of any disagreement or agreement with them, see "What Should We Do When We Disagree" for a related notion. 8 L.A. Paul, Transformative Experience (Oxford: Oxford University Press, 2014). transformative, in that they give you new information by virtue of a particular experience that	can	only	be	obtained	by	having that	experience.	Paul	has	argued	that we cannot rationally make decisions that will transform us because there is an asymmetry between	who	we are now, and	what	we know now, and	who	we	will be then. We cannot make a comparison between before and after to calculate the expected	utility, for	example,	adopting	a child	may	be	a	wonderful	experience for	my friend,	but	I	may	come	to	regret it.	Yet	we	often	make	life-changing	decisions:	moving country, getting married, or joining a religious denomination. Not all transformative experiences	are	the	result	of	conscious	decisions.	Becoming	long-term	ill	or	disabled	is	a situation	few	people	choose,	yet	it	transforms	what	they	know	(e.g.,	what	it	is	like	to	live in the face	of imminent	death),	and	who they	are (e.g., someone	who	became	blind). The	transformative	nature	of	disability is illustrated	by	how	disabled	and	non-disabled people	think	about	their	quality	of	life:	sighted	people	tend	to	think	being	blind	is	a	lot worse	than	blind	people	think	it	is,	including	blind	people	who	were	previously	sighted.9 Is	religious	conversion	transformative?	Saul/Paul's	conversion	to	Christianity	on the	road	to	Damascus	suggests	that	a	single	transformative	event	can	lie	at	the	basis	of conversion.	As	recorded	in	Acts	9	(in	a	third-person	narrative)	and	the	Pauline	epistles such as Galatians 1 (in a first-person narrative), Saul of Tarsus was a Jew who persecuted the early Christian community. On his way to Damascus, where he was extending his mission to have Christians imprisoned, he had a dramatic religious experience:	he	saw	a	blinding	light,	and	heard	the	voice	of	the	risen	Christ,	who	asked him	why	he	was	persecuting	him.	Saul	then	got	baptized,	and	started	missionary	work for the nascent Christian Church. This account of conversion in terms of a single dramatic experience shaped subsequent discussions of what conversion is like, for instance in the work of early psychologists such as William James.10 Subsequent research into religious conversions suggests a	more gradual pattern. Conversions are not single experiences, but rather the cumulative effect of	many smaller experiences and decisions. Even among people who self-identify as born-again Christians, the majority experience a gradual, rather than a sudden, conversion to Evangelical Protestantism.11 Nevertheless, religious conversions transform a person's system of beliefs	(thus	are	epistemically	transformative),	and	change	their	personality.	This	is	not so much a change in personality traits, but in goals, feelings, attitudes, and life meaning.12 Given that a person, post-conversion, is both epistemically and personally transformed, it	becomes	difficult to	gauge	whether	a former	epistemic	peer is still an epistemic peer. For example, Jonathan Edwards has an extensive record of the 9 Havi Carel, Ian J. Kidd, and Richard Pettigrew, "Illness as Transformative Experience," The Lancet 388 (2016): 1152–1153. 10 William James, The Varieties of Religious Experience. A Study in Human Nature (London: Penguin, 1902 [1985]). 11 Richard D. Dixon, Roger C. Lowery, and Lloyd P. Jones, "The Fact and Form of Born-Again Religious Conversions and Sociopolitical Conservatism," Review of Religious Research 34 (1992): 117–131. 12 Raymond F. Paloutzian, James T. Richardson, and Lewis R. Rambo, "Religious conversion and personality change," Journal of personality 67 (1999): 1047–1079. deepening	of	his	faith	in	several	phases: . . .	my sense of divine things gradually increased, and became	more and more lively, and had more of that inward sweetness. The appearance of everything	was	altered:	there	seemed	to	be,	as	it	were,	a	calm,	sweet	cast, or appearance of divine glory, in almost everything. God's excellency, his wisdom, his purity and love, seemed to appear in everything; in the sun, moon,	and	stars, in the	clouds	and	blue	sky, in the	grass, flowers, trees, in the	water	and	all	nature;	which	used	greatly	to	fix	my	mind.13 How	can	we	know	that	Edwards,	post-conversion,	is	in	an	epistemically	better	position than	before?	How	can	Edwards	himself	know	this	is	the	case? 3.	Disagreement	with	one's	former	self Conversion thus gives rise to two forms of disagreement-disagreement with one's	former	self,	and	disagreement	with	friends	and	family.	Let's	look	at	someone	like Catherine,	who is now in	disagreement	with	her former self. She	now	believes things she	would	have	found	implausible	just	a	year	ago.	Should	she	accord	more	credence	to her	new	beliefs?	If	conversion	were	solely	the	result	of	a	careful,	rational	deliberation,	it would seem proper that the convert is more confident about her beliefs postconversion.	However,	conversion	occurs	as	a	result	of	several	factors.	These	include	the desire to be of the same religious denomination of one's family and friends, or the desire	for	self-improvement	and	for	having	a	religion	that	is	more	in	line	with	one's	selfimage. For example, in a qualitative study on French young adults	who converted to Islam,	several	people	mentioned	that they	believed	regular	prayer	and	observing food taboos and the Ramadan would help them be more personally disciplined.14 Such concerns	may	be	practically	rational,	but	do	not	say	much	about	the	truth	or	falsity	of the	beliefs	one	adopts. The influential Lofland-Stark	model15 of religious conversion	outlines two	basic conditions that	prompt religious	conversion: first,	persons	must feel	an	acute	need	or tension within their religious problem-solving perspective, and second, they form affective bonds with members of the new religion/affiliation they convert to, which facilitates the step to the new religious movement. This model has attracted much attention	in	the	social	study	of	religion.	More	recent	sociological	accounts	of	conversion identify two types of attraction of religious	movements to new converts: ideological, 13 Jonathan Edwards, A Treatise Concerning Religious Affections, in Three Parts (Philadelphia: James Crissy, 1821), xxv. 14 Mounia Lakhdar, Geneviève Vinsonneau, Michael J. Apter and Etienne Mullet, "Conversion to Islam among French Adolescents and Adults: A Systematic Inventory of Motives," International Journal for the Psychology of Religion 17 (2007): 1–15. 15 John Lofland and Rodney Stark, "Becoming a World-saver: A Theory of Conversion to a Deviant Perspective," American Sociological Review 30 (1965): 862–875. through	offering	a	new	perspective	on	life,	and	social,	by	providing	a	satisfactory	social network.16 Thus, conversion seems to be to a large extent the result of irrelevant causal factors,	such	as	the	presence	of	social	groups	that	one	might	feel	at	home	with	and	seek closer	affiliation	with.	However,	one's	original	religious	beliefs	(or	lack	thereof)	are	also largely the result of irrelevant influences. Vavova defines an irrelevant influence as follows:17 An	irrelevant	influence	for	me	with	respect	to	my	belief	that	p	is	one	that (a)	has	influenced	my	belief	that	p	and	(b)	does	not	bear	on	the	truth	of	p. There	is	a	continued	debate	on	whether irrelevant influences	on	our	beliefs	can	act	as defeaters. This debate	often centers on the	question	of	whether our response to the evidence	allows	for	some	latitude,	as	permissivists	propose,	or	whether	a	total	body	of evidence	only	allows	for	one	rational	attitude,	as	proponents	of	uniqueness	hold.18 If we assume that sociologists are right and	most conversions are caused by a mixture of social and personal factors, few of which are relevant to the truth of the beliefs,	how	should	a	convert	evaluate	her	past	self's	beliefs?	Vavova	recommends	that in	order	to	evaluate	the	epistemic	significance	of	irrelevant	influences,	we	need	to	look at what causes these influences. If the influences give "good independent reason to think that you are	mistaken	with respect to p, you	must revise your confidence in p accordingly-insofar	as	you	can."19	For	instance,	if	a	belief	is	the	result	of	brainwashing or wishful thinking, this does seem to present substantial higher-order evidence that undermines the belief. Extreme cases of conversion that involve indoctrination or coercive	force	would	thus	be	cast	in	a	negative	light,	as	indoctrination	and	coercion	are in	general	poor	belief-forming	mechanisms.	But	for	many	other	cases,	which	involve	the typical mixture of social factors and personal motivations, it is not so clear whether these	irrelevant	influences	provide	the	convert	with	a	good	independent	reason	that	she is	mistaken	with	respect	to	her	new	beliefs.	The	factors	underlying	conversion	cases	do not seem to be	more epistemically vicious or benign than factors underlying original religious	belief	formation	(e.g.,	parental	religious	affiliation). A religious convert has one piece of higher-order evidence that someone	who does	not	convert	does	not	possess,	namely	first-personal	experience	of	changing	one's religious beliefs in a deep and significant way: the convert knows that her religious beliefs	can	be	changed.	This	is	in	addition	to	any	first-order	evidence	that	prompted	the conversion,	e.g.,	Paul's	religious	experience	on	the	Road	to	Damascus.	(Note	that	not	all 16 Willem Kox, Wim Meeus, and Harm 't Hart, "Religious Conversion of Adolescents: Testing the Lofland and Stark Model of Religious Conversion," Sociological Analysis 52 (1991): 227–240. 17 Katia Vavova, "Irrelevant Influences," Philosophy and Phenomenological Research (in press, online first), 3. 18 See for a defense of permissivism, Miriam Schoenfield, "Permission to Believe: Why Permissivism is True and What It Tells Us about Irrelevant Influences on Belief," Noûs 48 (2014): 193–218. For a defense of uniqueness, see Roger White, "Epistemic Permissiveness," Philosophical Perspectives 19 (2005): 445–459. 19 "Irrelevant Influences," 12. conversion cases involve such first-order evidence; some	may be purely the result of social	factors	and	do	not	offer	any	first-order	evidence,	but	then	the	convert	still	has	the second-order	evidence	of	having	converted).	This	might	lead	a	convert	to	become	more accepting	and	open	to	the	religious	views	of	others	(after	all,	the	convert	had	different religious beliefs prior to her conversion). If Catherine now holds beliefs she found implausible just a year ago, this tells her something meaningful not just about her current religious beliefs, but about the fragility and revisability of religious beliefs in general. Thus it would seem rational for a convert to remain open to the views of dissenting	epistemic	peers.	By	contrast,	Miguel	does	not	have	the	relevant	experiences that	presumably	were	at	least	in	part	the	basis	of	Catherine's	conversion.	Given	that	he has	not,	he	should	remain	open	to	the	possibility	that	Catherine	has	relevant	evidence that	he	lacks.	Thus,	conciliationism	seems	a	rational	response	in	the	light	of	conversion of	a	former	epistemic	peer.	I	will	look	in	more	detail	at	this	question	in	the	next	section. 4.	Disagreement	with	a	recently	converted	peer I	will	now	look	at	the	question	of	what	(if	any)	epistemic	conclusions	Miguel	can	draw from Catherine's conversion, in the absence of further information (let's assume Catherine	had	to	dash	to	the	airport;	so	Miguel	never	gets	to	hear	her	reasons).	Should it lower his confidence in his complacent atheism? One could argue that Catherine's conversion does not provide	Miguel	with any new information.	Miguel is presumably aware	of the	distribution	of	opinions	about theism.	He	knows that	most	of the	world population (about 85-90%) are theists (most of these are monotheists),20 and that a substantial	number	of	academics	(albeit	still	less	than	50%)	are	atheists.21	He	might	also know	that	73%	of	academic	philosophers	are	atheists.22	Since	Miguel	shares	most	of	his background	beliefs	with	academic	philosophers,	he	would	probably	consider	them	to	be his epistemic peers.	Miguel could	maintain his credences accordingly. There does not seem	to	be	any	special	information	gained	by	an	old	friend	having	converted	to	a	belief he	does	not	share. However, Miguel has acquired one new piece of information: someone with whom	he	had	many	background	beliefs	in	common,	and	whom	he	has	always	respected as his epistemic peer, changed her mind on the question of theism. If he considers Catherine to be similar to him in many respects (e.g., shared graduate school experience), they are similar in relevant background knowledge. Thus it would seem epistemically prudent for Miguel to at least follow up with Catherine (e.g., a simple email	saying	something	like,	"Hey,	Catherine.	It	was	great	to	meet	up	with	you.	I	have	to 20 Phil Zuckerman, "Atheism. Contemporary Numbers and Patterns." In The Cambridge Companion to Atheism, ed. M. Martin (Cambridge: Cambridge University Press, 2007), 47–65. 21 Neil Gross and Solon Simmons, "The Religiosity of American College and University Professors," Sociology of Religion 70 (2009): 101–129. 22 David Bourget and David Chalmers, "What do philosophers believe?" Philosophical Studies 170 (2014): 465-500, but see Helen De Cruz, "Religious Disagreement: An Empirical Study among Academic Philosophers," Episteme 14 (2017): 71–87. confess I	was a bit surprised that you're a theist now. Could you tell	me	more about it?").	Maybe	Catherine	has	reasons	that	Miguel	has	not	properly	considered. There is another reason why the conversion of a friend who was (at least previously) an epistemic peer is significant: we tend to attach more weight to the testimony	of	those	who	are	close	to	us	than	to	the	testimony	of	strangers.	Maybe	this	is because we can gauge the epistemic credentials of familiar individuals better. But familiarity	alone	does	not	explain	the	extra	weight	we	accord	to	those	near	and	dear	to us. After all, if that were the case, we	would put	more stock in former friends or in frenemies,	and	this	does	not	seem	to	be	the	case	(indeed,	we	tend	to	be	more	cautious when it comes to both categories). Being friends engenders epistemic partiality.23 Already	very	young	children	show	the	tendency	to	value	the	testimony	of	people	close to them more than the testimony of strangers.24 This heuristic makes sense in the context of epistemic vigilance: since we not only need to sort out accurate from inaccurate testifiers,	but	also those	who	are truthful from	deceitful, it	makes	sense to trust	people	who	are	well disposed toward	us. Thus	people	have	a tendency to	place selective	trust	in	people	they	see	as	benevolent:	people	with	whom	we	have	a	trusting relationship	are	less	likely	to	deceive	us.25 Trust in	friends	may	also	be	valuable	beyond	purely	epistemic	reasons, just like self-trust	is	intrinsically	valuable.26	Some	feminist	epistemologists	have	emphasized	the value	of	certain	kinds	of	partiality: intellectual theorizing	should	not	be	seen	as	purely dissociated	from	our	emotional	lives.27	For	such	reasons,	Miguel	should	be	more	diligent in following up Catherine's reasons for converting. And perhaps likewise, Catherine should	be	diligent in following	up	with	Miguel to	explain	her reasons for converting. I will	now look	at	a	case	study	of	conversion	that	will illustrate	why	reasoned	debate is the	proper	response	to	a	friend's,	and	one's	own,	conversion. 5.	Rational	argument	and	conversion The	African	theologian	and	church	father	Augustine	of	Hippo	(354–430)	converted	from Manichaeism	to	Christianity.	In	both	religious	traditions,	he	was	an	apologist,	a	teacher, and an evangelist. The letter De Utilitate Credendi (The Usefulness of Belief)28 is addressed to Honoratus, a student friend. Augustine converted his friend to Manichaeism	with	much	difficulty,	and in the letter	set	himself the	unenviable task to try	to	convince	his	friend	to	convert	to	Christianity.	But	why	should	Honoratus,	whom	he previously persuaded of the	merits of	Manichaeism, now trust Augustine? As Asiedu 23 Sarah Stroud, "Epistemic Partiality in Friendship," Ethics 116 (2001): 498–524. 24 Paul L. Harris and Kathleen Corriveau, "Young Children's Selective Trust in Informants," Philosophical Transactions of the Royal Society of London B 366 (2011): 1179–1187. 25 Dan Sperber, Fabrice Clément, Christophe Heintz, Olivier Mascaro, Hugo Mercier, Gloria Origgi, and Deirde Wilson, "Epistemic vigilance," Mind & Language 25 (2010): 359–393. 26 See, for a defense of the value of self-trust, Robert Pasnau, "Disagreement and the Value of Self-Trust," Philosophical Studies 172 (2015): 2315–2339. 27 Daniel Jayes O'Brien, "A Feminist Interpretation of Hume on Testimony," Hypatia 25 (2010): 632–652. 28 Augustine, "The Usefulness of Belief (De Utilitate Credendi)," in Augustine: Earlier writings, ed. J.H.S. Burleigh (Philadelphia: Westminster Press, 391 [1953]), 284–323. writes, For	Augustine	to	achieve	his	purposes,	Honoratus	would	have	to	be	persuaded of Augustine's trustworthiness while discounting Augustine's much earlier evangelistic	campaigns	as	a	Manichee.	Honoratus	would	also	have	to	grant	that Augustine	himself	had	not	been	deceived	a	second	time	as	he	appears	to	have been	misled	the	first	time	when	he	was	persuaded	by	the	Manichees.29 The letter is revealing in that Augustine does not point to his own conversion experience	as	a	source	of	knowledge,	as	he	does	elsewhere	(e.g., in	his	Confessions).30 Rather,	the	letter	focuses	on	biblical	hermeneutics	(the	discrepancies	between	the	Old and New Testaments, which Manicheans often pointed out as reasons to reject Christianity) and on high-level epistemological principles such as trust and credibility. The	letter	focuses	on	the	reasons	Manicheans	gave	for	rejecting	Catholic	doctrines,	and argues	that	these	reasons	were	mistaken.	In	this	way,	Augustine	argues	that	Honoratus' (and	his	former	self's)	reasons	for	accepting	the	Manichaean	doctrine	were	mistaken: Well,	they	harangued	at	great length	and	with	great	vigour	against	the errors	of	simple	people,	which	I	have	since	learned	is	extremely	easy	for anyone	to	do	who	is	moderately	educated;	and	if	they	taught	us	any	of their own doctrines	we thought	we	must	maintain it because nothing else	occurred	to	us	to	set	our	minds	at	rest.31 The passage in viii, 20 recounts Augustine's own faith journey (what born-again Christians	would	call	their	"testimony").	He	first	reveals	that	he	was	already	"in	a	state of	serious	doubt"	about	Manichaeism	when	he	last	parted	from	his	friend,	and	that	his doubt grew even	more after he saw the underwhelming performance by the famous Manichean	Faustus.	"You	remember,	his	coming	to	explain	all	our	difficulties	was	held out	to	us	as	a	gift	from	heaven.	Well,	I	recognized	that	he	was	no	better	than	the	others of	the	sect,	except	for	a	certain	eloquence	he	had."32 While	Augustine	does	not	use	his own	conversion	as	a	source	of	evidence	to	Honoratus,	he	nevertheless	presents	it	as	a model	that	Honoratus	can	emulate.	For	example,	he	draws	close	parallels	between	his own	former	doubts	(now	happily	resolved),	and	Honoratus'	present	doubts.	This	echoes the conciliationist position in the epistemology of disagreement,	where the beliefs of others	we	respect	as	our	peers	provide	significant	evidence	(in	part	because	our	peers may have reasons or arguments we may not have considered properly), and where these	beliefs	call	for	belief	revision. 29 F.B.A. Asiedu, "The Limits of Augustine's Personal Authority: The Hermeneutics of Trust in De utilitate credendi," in Augustine and Liberal Education, ed. K. Paffenroth and K.L Hughes (Lanham: Rowman & Littlefield, 2001), 124–145, 128. 30 Augustine, Confessions (Vol 1) (translated by W. Watts) (Cambridge, MA: Harvard University Press, (4th century AD [2006]). 31 The Usefulness of Belief, i, 2, 292. 32 The Usefulness of Belief, viii, 20, 306. The letter (particularly sections vii–xi) develops an intricate philosophy of testimony,	where	Augustine	asserts	that	all	knowledge	must	begin	in	trust	of	those	who have	proper	authority,	rather	than	in	reason.	He	gives	the	example	of	the	trust	we	place in	our	parents: .	.	.	how	will	children	serve	their	parents	and	love	them	with	mutual	dutifulness	if they	do	not	believe	that	they	are	their	parents.	That	cannot	be	known	by	reason. Who the father is, is believed on the authority of the mother, and as to the mother, midwives, nurses, slaves have to be believed, for the mother can deceive,	being	herself	deceived	by	having	her	son	stolen	and	another	put	in	his place.33 To Augustine, the chief problem with Manicheans is that they do not recognize the importance	of	trust	in	testimony	of	those	who	have	proper	authority.	Instead	they	hold up a	mirage of how	we should acquire beliefs: "they promise to give to those	whom they	attract	a	reason	even	for	their	most	obscure	doctrines."34	Thus,	they	are	not	being intellectually	honest	with	their	adherents	and	converts,	because	it	is	simply	not	possible to give reasons for obscure doctrines, without resorting to trust in authoritative testifiers.35 In	De	Utilitate	Credendi	Augustine	sees	testimony	merely	as	a	basis	of	belief.	In his	Confessions	(397-401)	he	also	regards	it	as	a	basis	for	knowledge.36	Yet,	in	the	former he	clearly	sees	testimony	as	a	precondition	for	knowledge,	as	many	people	would	lack the relevant reasoning skills to work out religious truths for themselves. Augustine draws	an	illuminating	parallel	between	friendship	and	trust	in	testimony.	Against	those who	do	not	think	that	testimony	can	be	a	useful	source	of	belief,	Augustine	argues,	"I	do not	see	how	anyone	who	accepts	that	as	true	can	ever	have	a	friend.	For if to	believe anything	is	base,	either	it	is	base	to	believe	a	friend,	or	without	such	belief	I	cannot	see how	anyone	can	go	on speaking	about friendship."37	While it is	not	explicit, it is clear that	Augustine	here	is	appealing	to	his	friend	to	read	his	arguments	with	more	charity and patience than he would read the arguments from a Catholic writer he does not know, namely with the charity one owes a friend. The tone throughout the letter underlines	this	point,	with	Augustine	frequently	expressing	understanding	at	what	must be a surprise to his friend, for example, "You are amazed, I am sure. For I cannot pretend	that	I	was	not	formerly	of	a	very	different	opinion";38	he	frequently	anticipates objections Honoratus might have, such as, "But you will probably ask to be given a plausible reason	why, in being taught, you	must begin	with faith and	not rather	with 33 The Usefulness of Belief, xii, 26, 313. 34 The Usefulness of Belief, ix, 21. 35 This holds also for those who study the sciences. At some point, one needs to trust those with authoritative knowledge, as it is impossible to experimentally verify everything for oneself. 36 Peter King and Nathan Ballantyne, "Augustine on Testimony," Canadian Journal of Philosophy 39 (2008): 195–214. 37The Usefulness of Belief, x, 23, 309. 38 The Usefulness of Belief, vi, 13, 301. reason."39 Overall,	De	Utilitate	Credendi	shows	a	good	model	of	peer	disagreement in	the face	of conversion.	Augustine's aims in the letter are	modest. As he	points out in his closing paragraphs, he does not refute the Manichean doctrines or defend Catholic ones.	Rather,	he	aims	to	show	that	the	arguments	that	Manicheans	have	offered	against Catholic doctrines (namely, alleged discrepancies between the Old and New Testaments) are not as strong as he previously believed. He also argues that Manicheism	does	not	live	up	to	its	own	standards	of	belief	based	on	reason,	rather	than testimony-a	standard	that	Augustine	also	demonstrates	to	be	unattainable.	Along	the way, Augustine can also demonstrate to himself (as he also did at length in his Confessions)	that	he is	now	in	a	better	epistemic	position	than	his	pre-conversion	self. Even though Augustine may not be justified in thinking he now holds the correct doctrines, his new beliefs are based on more sophisticated grounds, whereas his previous	reasons	for	rejecting	Catholic	doctrines	proved	to	be	inadequate. 6.	Conclusion The	case	of	religious	conversion	presents	a	series	of	difficulties	for	traditional	accounts of	epistemic	peer	disagreement,	because	conversion	is	a	transformative	experience:	it	is difficult	to	compare	whether	a	convert	is	in	a	better	epistemic	position	post-conversion. Conversion is rarely the outcome of a rational decision process, but the result of irrelevant	causal	factors	such	as	the	religious	views	of	friends	and	personal	tension.	This was	almost	certainly	the	case	for	Augustine,	as	we	can	see in	passages	throughout	De De Utilitate Credendi, for example, "When I departed from you across the sea I was already	in	a	state	of	serious	doubt;	what	was	I	to	hold;	what	was	I	to	give	up?	Indeed	my hesitation	grew	greater	day	by	day from	the time that I	heard the famous	Faustus."40 Most cases	of conversion	are	not caused	by forces that	are	more	pernicious than the ones	that	gave	rise	to	the	original	set	of	beliefs	(e.g.,	beliefs	of	one's	parents).	Given	that both	self-trust	and	trust	in	friends	is	valuable	(for	epistemic	and	non-epistemic	reasons), it	does	not	seem	wrong	to	accord	prima	facie	weight	to	a	friend's	new	set	of	beliefs,	if one saw this friend as an epistemic peer prior to conversion. Rational argument and dialogue, as illustrated by Augustine, can play a crucial role in evaluating peer disagreement	caused	by	conversion.	It	not	only	helps	one's	friends	to	critically	evaluate their	beliefs,	but	also	allows	the	convert	to	critically	reflect	on	her	own. 39 The Usefulness of Belief, ix, 22, 308. 40The Usefulness of Belief, viii, 20, 306.