Brentano's	lectures	on	positivism	(1893-1894)	and	his	relationship	to	Ernst	Mach Denis	Fisette Université	du	Québec	à	Montréal Abstract: This paper is mainly about Brentano's commentaries on Ernst Mach in his lectures "Contemporary philosophical questions" which he held one year before he left Austria. I will first identify the	main sources of Brentano's interests in Comte's and J. S. Mill's	positivism	during	his	Würzburg	period.	The	second	section	provides	a	short	overview of	Brentano's	1893-1894	lectures	and	his	criticism	of	Comte,	Kirchhoff,	and	Mill.	The	next sections	bear	on	Brentano's	criticism	of	Mach's	monism	and	Brentano's	argument	against the	reduction	of	the	mental	based	on	his	theory	of	intentionality.	The	last	section	is	about Brentano's	proposal	to	replace	the	identity	relation	in	Mach's	theory	of	elements	by	that	of intentional	correlation.	I	conclude	with	a	remark	on the	history	of	philosophy	in	Austria. In	his	article	"My	last	wishes	to	Austria",	written	just	before	he	left	Vienna	in	1895,	Franz Brentano	(1929c,	p.	10)	recalls that,	as	he	was	appointed in	Vienna in	1874, the	Austrian minister entrusted him the task to implement, in Austria, "the seeds of a genuine philosophy"	at	a	time	when	most	philosophy	chairs	in	Austria	were	occupied	by	Herbart's disciples.	This	project stands	out	clearly in several lectures	delivered	by	Brentano	during his Vienna period (1874-1895), particularly in his inaugural address at the	University of Vienna entitled "On the reasons for	discouragement in the field of philosophy".	Brentano (1929a) addresses the	prejudice that philosophy	had	become an obsolete discipline	with regard	to	the	remarkable	development	of	natural	sciences,	and	his	purpose	was	to	interest the	young	Austrians	in	a	new	program	based	on	the	principles	of	an	empirical	philosophy. As	Oskar	Kraus	(in	Brentano,	1929,	p.	157)	rightly	pointed	out	in	his	edition	of	this	writing, the	philosophical	program	that	Brentano	outlines in	his inaugural	address is	based, if	not directly	on	Comte's	positive	philosophy	as	such,	at	least	on	the	outcome	of	his	research	on Comte's and Mill's positivism during his Würburg period. This program has been systematically	developed	in	Brentano's	Psychology	from	an	empirical	Standpoint	published	a few	months	after	his	inaugural	address. As	Brentano	makes	it	clear	at	the	very	beginning	of this	work,	he	advocates	a	philosophy	of	experience,	which	is	akin	to	the	task	and	method	of natural	sciences. Brentano	continued	to	attach	much	importance	to	positivism	during	the	Vienna	period	and later in	Florence	as	evidenced	by	the	notes,	which	he	dictated	during	the	winter	of	19051906	and	published	under the title	Über	Ernst	Machs	'Erkenntnis	und	Irrtum'. Less	known perhaps	are	Brentano's lectures	"Contemporary	philosophical	questions"	which	he	held	in Vienna one year before he left Austria and in which he extensively discusses Mach's positivism.	In	these	lectures,	Brentano	examines	four	versions	of	positivism,	that	of	Auguste Comte, which he compares with Kirchhoff's descriptivism, and Mach's phenomenalism, which	he compares	with John	Stuart	Mill's empiricism.	Brentano claims that the last two versions	of	positivism represent a	progress	over the	other two	versions, namely	because they	are	up	to	date	with	respect	to	the	development	of	natural	sciences,	and	because	they recognize the philosophical value of the field of mental phenomena, i.e. descriptive psychology. Brentano's correspondence with Husserl (1994) and Mach (Brentano, 1988) in 1895 testifies that, despite his reservations regarding the	metaphysical positions advocated in these	different	versions	of	positivism,	there	remains,	however,	a	"consensus	on	the	method of research," namely with Brentano's methodological phenomenalism. What Brentano criticizes	in	Mach's	monism,	is	the	identification	of	physical	and	mental	phenomena	and	he argues against Mach that the two classes of phenomena are irreducible to one another. Moreover,	Brentano	raises the	question	as to	whether,	with	some	modifications, it	would not	be	possible	to	preserve	the	essential	of	Mach's	theory	of	elements	and	he	proposes	to replace	the	identity	relation	between	the	two	classes	of	phenomena	by	that	of	correlativity (Correlativität) through	which	he	characterizes	namely the intentional	relation	between	a psychical	phenomenon	and	its	object. 1. Brentano's	background	and	the	sources	of	his	interests	in	positivism In	1869,	Brentano	held	a	series	of	public	lectures	on	Comte	and	published,	in	the	Catholic journal Chillianeum, an article entitled Auguste Comte and positive philosophy, which Brentano considered the first of a series of seven articles that he planned to write on Comte's	philosophy	(Brentano,	1869).	Even if this	project	has	never	been	carried	out, the question	arises	as	to	why	the	young	Brentano	was	so	much	interested	in	positivism	and	in Comte's philosophy in particular. As a first approximation, there are several aspects of Comte's	philosophy in	Brentano's	paper	on	Comte,	which	were	already	at the	heart	of	his philosophical preoccupations in the first years of his professorship in Würzburg. First, according	to	the	fourth	thesis	in	Brentano's	habilitation	in	1866,	philosophy	must	adopt	the method of natural sciences. The importance of this thesis in Brentano's philosophy is attested at several places in his writings and namely in his paper on Comte where he emphasizes the importance of using the inductive method in philosophy. Secondly, Brentano's	criticism	of	speculative	philosophy	in	his	early	Würzburg	period	is	akin	to	that which	Comte	directed	against	metaphysical	and	theological	explanations	in	his	three	states law.	This	stands	out	clearly in	Brentano's	habilitation	talk from	1866 in	which	he	harshly criticises	Schelling's	speculative	philosophy	(Brentano,	1929d). A third important factor lies in Brentano's philosophy of history,	which is known as the theory of the four phases in the history of philosophy and which is, in many respects, compatible	with	Comte's	three	states	law	(Brentano,	1998).	Brentano	claims	that	there	are regularities in	the	course	of the	history	of	philosophy	since	the	pre-Socratics	and	one	can observe,	within	each	of	the	three	major	philosophical	periods,	four	phases	or	moments:	the first	stage	is	ascending	while	the	three	following	phases	mark	its	gradual	decline.	Brentano considers that his time belongs to a state of decline as shown by the place assigned to German	idealism	in	his	theory.	Brentano's	evaluation	raises	the	important	issue	as	to	what is	likely	to	take	over	from	this	phase,	which	Brentano	describes	as	one	of	extreme	decline. We	find	a	clear	answer	to	this	question	in	his	paper	on	Comte	where	Brentano	says	that	his time is ready for "a	positive treatment of philosophy" (Brentano, 1869, p. 133)	Brentano saw	in	the	positivist	treatment	of	philosophy	the	signs	of	an	ascending	stage	in	the	history of	philosophy	after	the	decline	of	idealistic	systems. But	the	most	important	factor	lies	in	the	importance	he	attached	to	British	empiricism	and to J. Stuart Mill's philosophy in particular. J. S. Mill's book	Auguste Comte and positivism drew	Brentano's	attention	to	Comte's	philosophy	and	it	stands	out	clearly	from	Brentano's paper	on	Comte	that	his	own	interpretation	owes	much	to	Mill's	work	(Mill,	1969).	This	is confirmed	by	a	letter	from	Brentano	to	Mill	(February	1872)	in	which	he	acknowledges	his debt to Mill's scientific contribution and thanks him for having drawn his attention to Comte's	philosophy	and	to	have	awakened	in	him	a	new	hope	for	the	future	of	philosophy. Brentano	complained to	Mill of the	deplorable state	of	philosophy in	Germany	and	of	his intention to undertake a reform of philosophy based on that of natural sciences along positivist	lines.	He	was	pleased	to	see	that	his	ideas	were,	in	many	respects,	similar	to	those of	Mill, particularly	with regard to the	method and, as	we shall see, to	Mill's doctrine of permanent	possibilities	of	sensation1. In his article on Comte, Brentano (1869) examines several aspects of Comte's Cours de philosophie	positive	which	had	a	direct impact	on	Brentano's	philosophical	program	in	his Psychology	from	1874.	The	first	aspect	pertains	to	the	nature	of	phenomena.	The	notion	of phenomenon such as	Comte	uses it in his	work is particularly important for	Brentano in light of its central role in Brentano's Psychology where	mental and physical phenomena constitute	the	object	of	psychology	(psychic	phenomena)	and	natural	sciences	(the	physical phenomena) respectively. That is why P. Simons, and more recently Tim Crane (2014), attribute to	Brentano	a form	of	methodological	phenomenalism	whose	origin is in	Comte. Secondly, Brentano considers that, with some	modifications, Comte's three states law is compatible with his own theory of the four phases that I mentioned above. Brentano further agrees	with	Comte that natural sciences are solely concerned	with the	discovery, through the observation of individual cases, of relations of similarity and succession between	phenomena,	which	fall	under	general	laws.	The	main	task	of	science	is	therefore	to look	for	general	laws	that	govern	these	relations	and	to	reduce	them	to	the	lowest	possible number. Finally, Comte has had a lasting influence on Brentano's classification of sciences. Brentano's	main reservation regarding Comte's classification is clearly formulated at the 1	Moreover,	in	the	summer	of	1872,	Brentano	made	a	trip	to	England	in	order	to	meet	J.	Stuart	Mill and	several	British	philosophers.	Unfortunately,	this	encounter	with	J.	S.	Mill	never	took	place,	but we	know	that	he	met	H.	Spencer	and	several	influential	British	philosophers	(Fisette,	2014a). very	end	of	his	paper	where	he	criticizes	Comte	for	not	admitting,	in	his	own	classification, two disciplines which constitute the two main axes of Brentano's philosophy, i.e., metaphysics	and	psychology.	Brentano	opposes	to	Comte's	classification	that	proposed	by Aristotle and he refers to Aristotle's De Anima where psychology is considered the philosophical	science	par	excellence.	However,	Brentano	claims	that	the	recognition	of	the status of science to psychology does not compromise the value of Comte's theory of the three states, nor the principles of his classification. On the contrary, says Brentano, it confirms	them.2 2.	Brentano's	lectures	"Contemporary	philosophical	questions":	an	overview The	main	part	of	Brentano's	1893-1894 lectures "Contemporary	philosophical	questions" bears	on	positivism	and	monism	in	Comte,	Kirchhoff,	Mach,	and	J.	S.	Mill	(p.	29376	et	sq.). The	manuscript is divided into two parts. In the first part, Brentano compares Comte's positive	philosophy	with	Kirchhoff's	descriptivism,	(p.	29378	f.)	while	in	the	second	part	(p. 29410	f.),	Brentano	compares	J.	S.	Mill's	philosophy	with	Mach's	phenomenalism.	I	will	first very	briefly	summarizes	Brentano's	analysis	of	the	three	first	versions	of	positivism	before examining,	more	extensively,	Brentano's	position	vis-a-vis	Mach's	phenomenalism. First	of	all,	these	four	versions	of	Positivism	have	several	points	in	common,	beginning	with the	importance	they	attach	to	the	description	of	phenomena.	Brentano	is	in	agreement	with this	aspect	of	descriptivism	which favours the	"how"	question	over the "why"	question in the	sense	that	the	description	of	phenomena	is	prior	to,	and	a	necessary	condition	to	their explanation.	This	trait	can	also	be	found	in	Brentano's	lectures	on	descriptive	psychology,	in which he distinguishes, within psychology, genetic or physiological psychology from descriptive	psychology	and	in	which	he	emphasizes	the	primacy	of	description	and	analysis of	psychical	phenomena	over	the	causal	explanations	by	genetic	psychology.	Descriptivism is	mainly	associated	in	these	lectures	with	the	school	of	Kirchhoff in	physics	and	with	the task	assigned to	mechanics to	describe the	movements in	nature in the simplest	possible way	(p.	29381).	The	requirement	of	simplicity in	description is	also found in	Comte,	who assigns	to	sciences	to fix	the laws	which	govern	the	relations	between	phenomena	and	to reduce them to the smallest	possible	number. In	Mach, it corresponds to the	principle	of economy	of	thought	(Mach,	1903). What Brentano criticizes in his lectures is the unknowable nature of causes and the rejection	of explanations	based	on the	primary causes	of	observed	phenomena.	Brentano admits that	Comte, for	example,	does	not	exclude the	existence	of	causes,	but	he	believes that	Comte	and	Kirchhoff	are	unjustified	to	affirm	that	an	advanced	science	renounces	the search	for	causes	(p.	29403).	Brentano	argues	that	natural	sciences	are	not	limited	to	what 2	I	have	argued	elsewhere	that	all	these	elements	are	part	of	Brentano's	program	of	a	psychology	as a	science,	which	he	develops	during	his	Vienna	period	(Fisette,	2014a;	see	Münch,	1989). is given directly in experience and that the concept of cause can not be	wholly excluded from	the	natural	sciences	as	most	positivists	believe.	Brentano	claims	that	explanations	in scences	are	irreducible	to	descriptions	and	they	in	fact	require	causality: Dass vielmehr 1. die Annahme der Existenz von Bewegungen <von bewegter Materie> zur Erklärung der psychischen Phänomene schon etwas anderes als Beschreibung	von	Bewegungen ist und	2. im	besonderen	nur	unter zu	Hilfenahme des	Causalbegriffes	begründet	werden	könnte	(p.	29408-29409). Brentano rejects these two versions of positivism advocated by Kirchhoff and Comte because,	according	to	him,	every	advanced	science	does	not	renounce	explanations	which resort	to	causality	and	the	first	two	versions	of	positivism	are	therefore	lagging	behind	the development	of	sciences.	Brentano	then	wonders	whether,	in	view	of	these	objections,	one should rule out any form of positivism or consider other versions even if they are to be critically complemented. He opted for the second option and proposed to examine the versions	proposed	by J. S.	Mill (1865) and	E.	Mach (1914, 1891, 1892). I shall first say a word	about	J.	S.	Mill's	permanent	possibility	of	sensation,	and	then	turn	to	the	position	of Mach	in	the	next	sections. Brentano	maintains	that,	for	all	four	versions	of	positivism,	the	objects	of	experience	are,	in one	way	or	another,	reducible	to	one's	own	mental	phenomena	and	to	percepts	in	the	case of	sensory	perception.	For	if	phenomena	are	somehow	related	to	experience,	then	they	are necessarily	related	to	mental	states	(sensory	perception).	In	other	words:	esse	est	percipii.	It follows	that	"only	our	own	psychical	phenomena	deserve	the	name	of	facts	of	experience" (p.	29411).	Through	this	doctrine, J.	S.	Mill	seeks	to	account	for	the	way	in	which	one	can believe in the existence of a spatial outer	world from the data of sensory experience (p. 29423).	According	to	Mill,	our	representation	of	the	external	world	contains,	in	addition	to the sensations which are momentary and fleeting, a multiplicity of possibilities of sensations which come to us, in part, from past experiences or observations and which indicate	that	under	certain	circumstances,	one	can	experience it	again.	Mill further	claims that sensations change	while these possibilities persist or are permanent (1865, p. 237238).	Brentano	argues that	Mill's	philosophy	marks	an improvement	over those	of	Comte and	Kirchhoff	not	only	because	he	takes	into	account	the	domain	of	mental	phenomena	but also	because	he	admits	the	possibility	of	the	knowledge	of	causes	and	causal	laws.3 3.	Mach's	psychophysical	identity	and	his	theory	of	elements Brentano's position towards positivism is not very different from that	which he adopted during	the	Würzburg	period	with	regard	to	Comte	and	J.	S.	Mill.	As	it	is	clearly	stated	in	his 3	In	his	Psychology,	Brentano	refers	to	Mill's	doctrine	in	relation	to	his	definition	of	natural	sciences as	a	science	of	physical	phenomena,	and	proposed	a	definition	of	the	object	of	natural	sciences	along Comtian	lines;	in	this	context,	he	compares	his	concept	of	force	to	Mill's	permanent	possibilities	of sensation	(2009,	p.	76). letter	to	Mach	that	I	mentioned	earlier,	there	is	an	"agreement	on	the	method	of	research," in that both share methodological phenomenalism. However, Brentano unequivocally rejects	phenomenalism	associated	with	a	kind	of	neutral	monism,	according to	which the world is made of neither matter nor spirit, but of a neutral stuff, which can be treated according to the context, interests and the direction of research as mental or material. Neutral	monism	also	refers	to	a	metaphysical	position	which	affirms	that	the	uniqueness	of reality and its neutrality with respect to whether it is physical or psychical. Mach thus defends an anti-metaphysical position insofar as he believes that everything which goes beyond	what	is	immediately	given	is	metaphysical	and	any	science	which	does	not	conform to	pure	description	is	merely	dealing	with	Scheinprobleme.	As	Brentano	explains: Mach erklärt darum die räumliche Aussenwelt und alles was man von Bewegungsvorgängen in ihr anzunehmen pflegt verwerfen zu müssen, weil diese Annahmen innerlich absurd seien. Die Forscher,	meint er, schienen allerdings in | der Verfolgung wissenschaftlicher Probleme in rechtmässiger Weise zu ihnen zu gelangen.	Aber	dennoch	sei	es	unvernünftig	daran	zu	glauben	(p.	29429-29430). Mach's	position	rests	on	his	doctrine	of	elements	and	involves	a	rejection	of	metaphysical assertions	on	the	realities	of	the	external	world,	and	Mach's	monism	has	the	consequence	of reducing the world and all that it contains to functional relations and combinations between	sensations. Brentano advocates instead a form	of critical realism according to	which the only access one	has	to	the	external	world	is	by	means	of	phenomena	through	which	they	are	given	to us; but these objects exist independently of being perceived. And this form of critical realism	is	compatible	with	methodological	phenomenalism.	Moreover,	Brentano	also	denies Mach's	thesis	according	to	which	the	task	of	science	is	merely	to	describe	and	not	to	explain phenomena	and	argues,	as	he	did	against	Kirchhoff	and	Comte,	that	"it	is	unfair	to	claim	that advanced	sciences	renounces	the	search	for	causes"	(p.	29403). Brentano focuses on two important points in his analysis of Mach: the non-reality of a spatial	world	and	the	identity	of	the	two	classes	of	phenomena.	Brentano	claims	that	Mach's phenomenalism	and	his	proof	of	the	absurdity	of	a	spatial	external	world	are	grounded	on the	identity	of	the	mental	and	the	physical in	sensations,	which	Mach	clearly	stated	at	the very	beginning	of	The	Analysis	of	sensations:	"I	see	no	opposition	of	physical	and	psychical, but	simple identity	as	regards	these	elements. In the	sensory	sphere	of	my	consciousness everything is at once physical and psychical" (Mach, 1914, p. 44; see p. 310). And this identity is based, in turn, on Mach's theory of elements and functional dependencies of sensory	elements	on	one	another. Mach's theory of elements is a system of general principles on the immediate data of experience.	The	basic	idea	is	to	consider	the	psychological	or	physical	objects	as	a	complex of elements,	which are	bound together	by functional relations	of	dependence	of	different kinds.	The	essential	difference	between	these	classes	of	relations,	and	namely,	between	the relation	to	a	physical	object	and	that	to	a	mental	state,	for	example,	depends	on	whether	the elements	overlap	the	sensory	surfaces	or	the	periphery	of	our	senses. To	be	more	precise, the	boundary that	delineates	what	belongs to the	physical and to the	mental	depends	on what	he	calls	"a	spatial	delimitation	U	of	our	own	body"	or	the	flesh.	For,	since	the	sensory world belongs simultaneously to the physical and to the psychical world, the difference between	physics	and	the	physiology	of	senses, for instance,	depends	primarily	on	the	fact that	the	latter	only	takes	into	account	our	own	body	(i.e.	our	nervous	system).	The	function U	makes it	possible	both to	present the functional relations	between the	elements	and to distinguish	the	physical	from	the	psychological	in	a	non-substantialist	way. The	three	more	important	classes	of	relation	structuring	the	elements	are	the	following: 1a.	Relations	of	physical	dependence:	relations	between	items	A,	B,	C,	etc.	outside	of U; 1b.	Neurophysiological	relations	of	dependence:	relations	between	the	elements	K,	L, M,	etc.	inside	of	U; 2.	Psychophysiological	relations:	relations	between	elements	inside	and	outside	of	U, i.e.,	relations	between	1a	and	1b; 3.	Relations	of	psychological	dependence: relation	between	elements	a,	b, c, etc. to which	correspond	mental	states	or	mental	phenomena	such	as	presentation,	feeling, judgment,	etc. Each	variable	takes	its	value	only	when	it	takes	place	in	a	physical	or	psychophysiological relation. For instance, the elements A, B, C refer to physical objects, physical properties, psychological	objects,	or	sensations	only	insofar	as	they	take	place	in	a	relation	of	physical dependence (i.e. relations 1a and 1b), a psychophysiological dependence (relation 2), or psychological	dependence	(relation	3).	To	quote	Mach	again: A	color	is	a	physical	object	as	soon	as	we	consider	its	dependence,	for	instance,	upon its luminous source, upon other colors, upon temperatures, upon spaces, and so forth.	When	we	consider,	however,	its	dependence	upon	the	retina	(the	elements	K, L,	M, etc.), it is a psychological object, a sensation.	Not the subject	matter, but the direction	of	our	investigation,	is	different	in	the	two	domains	(1914,	p.	17-18). This holds	a fortiori for the subject,	which	Mach understands as a complex of functional relations	of	a	certain	kind.	It	follows	that	the	subject	matter	of	all	sciences	is	the	same,	i.e. the	elements	and	functional	relations	between	them,	whereas	their	differences	rest	on	one's stance	toward	them	and	in	the	interests	and	orientation	of	the	research. 4.	Argument	de	Brentano	contre	la	thèse	de	l'identité:	intentionnalité As	I	said,	Mach's	doctrine	of	elements	amounts	to	identifying	what	Brentano	considers	two irreducible	classes	of	phenomena.	It	therefore	does	not	account	satisfactorily	for	the	duality in	the	percept	or	in	one's	state	of	mind	such	as	an	emotion	between	the	feeling	and	what	is felt, or between perceiving and	what is perceived. According to Brentano, to this duality correspond	two	classes	of	phenomena,	which	are	bearers	of	heterogeneous	and	irreducible proprieties,	and	this	identification	is	therefore	absurd	(Brentano,	1988,	p.	28;	67f.).	For	this identification	would amount to identifying „das Sehen der Farbe und die Farbe und das Hören des Schalls und der Schall u.s.w. identisch seien. Wie keine Empfindung ohne immanentes	räumliches	Objekt,	so	könne	also	auch	kein	Räumliches	anders	denn	als	Objekt unseres	Bewusstseins	bestehen"	(p.	29433). In his Psychology, Brentano had already considered a similar hypothesis which he attributed to Alexander Bain and J. Stuart Mill in the context of the distinction between primary	and	secondary	objects	and	it	consists	merely	in	identifying	primary	and	secondary objects. Brentano's main argument against this identification rests on the view that the essential	properties	of	the	class	of	mental	phenomena	are	not	attributable	to	the	other	class and	vice	versa	(2009,	p.	94-95).	There	is	thus	irreducibility	of	the	object	seen	to	the	vision of	the	object,	and	as	Brentano	explains	in	Sinnespsychology,	when	one	says	that	the	primary and	secondary	objects	appear	simultaneously	to	consciousness,	"appearing	simultaneously does	not	mean	appearing	as	the	same"	(1907,	p.	96). Brentano's argument against this identification is systematically developed in the first chapter of the second book of his	Psychology where he discusses several criteria for the delineation	of	the	mental	from	the	physical. Concretely,	in	the	case	of	the	color	green,	the vision	of	green	is	a	psychical	phenomenon,	which	is	about	the	color	green,	while	the	seen color, which Brentano conceived of in 1874 as an immanent object of presentations, belongs to the class of physical phenomena (p. 29439). The following quote from Brentano's	lectures	summarizes	Brentano's	position	on	that	issue: Sensing (das	Empfinden) always has the general characteristic feature of a	mental phenomenon, which is characterized as an intentional relation to an immanent object. It can be found similarly in memorising, desiring, enjoying, recognizing, negating, etc. However, what is felt [in sensing] has the general character of a physical	phenomenon,	which	consists	in	the	fact	that	the	phenomenon	is	localized	(p. 29441). Brentano concludes that Mach's proof of the "absurdity of the assumption of a spatial outside	world	on	the	basis	of	the	identity	of	the	mental	and	the	physical	in	sensations	is	a complete	failure"	(29443). 5.	Identity	versus	correlation Now, if one accepts with Brentano the irreducible character of these two classes of phenomena, the question arises as to whether, with some modifications, it might be possible to preserve the core of Mach's conception (p. 29444). Brentano responds positively, provided that one replaces the identity relation between the two classes of phenomena	by	that	of	correlativity	(Correlativität),	which	Brentano	(1982)	has	introduced in	his	lectures	on	descriptive	psychology	held	in	Vienna	in	the	late	1880s.	In	these	lectures, Brentano	advocates	a	relational	theory	of intentionality,	which	relates	mental	states	to its objects:	"As	in	every	relation,	two	correlates	can	be	found	here.	The	one	correlate	is	the	act of consciousness, the other is that <thing>	which it is directed upon. Seeing and	what is seen,	presenting	and	what	is	presented,	[...]	etc."	(1995,	p.	23-24).	Brentano	maintains	that what	is	specific	to	an	intentional	relation	is	that	it	includes	a	pair	of	correlates	of	which	only one	is	real	whereas	the	intentional	correlate	or	the	immanent	object	is	not	real	(1995,	p.	23 f.).	To	be	more	precise,	the	term	correlation	refers	in	this	lecture	to	the	bilateral	relation	of dependence between pairs like cause and effect, larger and smaller, etc. Brentano's proposal mainly pertains to this class of correlates which he calls intentional correlates (intentionales	Korrelat)	and	which	are	involved	in	the	relation	between	these	two	classes	of phenomena.	Examples	of	intentional	correlates	include	the	pairs	presenting	and	presented, perceiving and perceived, sensing and sensed, judging and judged, loving and loved, etc. Brentano	maintains	that	what	is	specific	to	this	class	of	intentional	relations	lies	in	the	fact that	it	includes	a	pair	of	correlates,	of	which	"only	one	is	real,	while	the	other	is	not." In short, Brentano considers in his lectures on positivism that this idea of correlation, broadly	understood,	is	something	similar	but	more	appropriate	to	what	Mach	was	looking for	with	his	doctrine	of	elements. The relation is that between subject and object. And this certainly has to do	with what	others like	Mach	(and	Lotze, for	example)	explained	by	saying that it is	clear from	the	outset	that	there	can	be	no	color	without	an	act	of	seeing	(Sehen).	But	they finally	say	nothing	about	space,	magnitude,	gestalt	and	movement.	However, let	us consider	that	we	also	have	a	presentation	of	these	items	as	we	have	a	presentation	of colors and sounds (...) through sensation; then it seems that, to be consistent, one must	also	maintain, in the	same	way, that	magnitudes,	gestalt,	movement, in	short, all that is spatial, would never be able to exist (bestehen) if not as correlates of sensations and to entertain a subject-object relation	with the latter. The opposite would be absurd. And we will have something essentially similar to what Mach wanted [with	his	doctrine	of	elements]	(p.	29444-29445). 6.	Final	remarks Brentano referred to his lectures on positivism in a letter to	Mach from	May 1895. This letter has a particular significance because it is addressed to the one	who	was called to succeed	him	in	Vienna	as	Chair	of	history	and	theory	of	the	inductive	sciences, left	vacant since Brentano's resignation in 1880. Brentano informed Mach about his lecture on positivism: You probably do not know that, by happenstance, in the first part of the lecture I taught last winter on the theme of positivism and monism, I addressed your positions on that theme in detail. I considered Comte and Kirchhoff as the representatives	of	a thoughtless	positivism,	whereas I	considered	J.	Stuart	Mill	and Mach	as	the	representatives	of	an	evolved	positivism.	However,	I	attempted	to	show why	one	form	or	another	of	positivism	proves	to	be	untenable.	[...]	I	am	and	always have been convinced that consensus on	mere wording-even if its significance is great-is	of	less	import	than	consensus	on	research	methods"	(1988,	p.	204). This excerpt shows that despite his reservations with respect to positivism, his views regarding	research	methods, i.e.	methodological	phenomenalism,	remained	similar	to	that he	adopted	upon	has	arrival	in	Vienna. There are also reasons to believe that Brentano's students in Vienna shared his opinion about Mach. Indeed, in September 1894, Mach was invited to the congress of the Association	of	German	physicists	and	naturalists	held	in	Vienna	and	he	gave	a	talk	entitled "The	principle	of	comparison	in	Physics".	Alois	Höfler,	a	student	of	Brentano	and	Meinong, invited	Mach	to	discuss	his	talk	at	a	meeting	of	the	Philosophical	Society	of	the	University	of Vienna. This	discussion	aroused	so	much	interest	that	two	further	sessions	were	organized by	Josef	C.	Kreibig,	another	student	of	Brentano.4	These	discussions	have	convinced	several members of the Philosophical Society of the interest of Mach's candidature to occupy Brentano's	chair.	Mach	began	his	teaching	in	Vienna	in	1895	and	we	know	the	influence	he had	on the course	of the	history	of philosophy in	Austria (Stadler, 1997).	But	Brentano's contribution	to	this	chapter	is	not	to	be	overlooked. Indeed, Brentano's program that I have mentioned earlier constitutes the philosophical program,	which	Brentano, despite his precarious academic situation in	Vienna, sought to establish in Austria. This program represents the starting point and the basis of the philosophy	of	his	students	in	Vienna,	although	Meinong,	Ehrenfels,	Twardowski,	Hillebrand, and Husserl, for example, have departed significantly from Brentano's original program. However, this program constitutes one of the main axis in the history of philosophy in Austria and it also represents an important reference for the Austrian members of the Vienna	Circle. In	any	case, it is clear that	when	Neurath (1935) claims, in	his remarkable book	on	the	development	of	the	Vienna	Circle,	that	the	latter	is	nothing	but	a	radicalization of	the	empiricists	trends	in	Vienna,	he	not	only	had	Mach	and	his	followers	in	mind,	but	also Brentano	and	his	successors	in	Austria. References Brentano,	F. − (2009)	Psychologie	vom	empirischen	Standpunkte	(1874),	M.	Antonelli	(ed.),	Schriften I,	1,,	Frankfurt:	Ontos	Verlag,	2008;	Psychology	from	an	Empirical	Standpoint,	tramns. A. C. Rancurello, D. B. Terrell, D. B., and L. McAlister, London and New York: Routledge, cited	as	Psychology. − (1998)	"Die	vier	Phasen	der	Philosophie	und	ihr	augenblicklicher	Stand",	in	O.	Kraus, (ed.),	Die	vier	Phasen	der	Philosophie	und	ihr	augenblicklicher	Stand,	Stuttgart:	Cotta, 1895, pp. 1-31; The Four Phases of Philosophy, trans. B. Mezei & B. Smith, Amsterdam:	Rodopi,	1998. 4	The	young	Husserl	was	also	very	much	interested	in	Mach	and	he	reviewed	Mach's	1893	paper (see	Fisette,	2015). − (1988) Über Ernst Machs 'Erkenntnis und Irrtum', R. Chisholm & J. Marek (eds.), Amsterdam: Rodopi. − (1982) Deskriptive Psychologie, R. Chisholm & W. Baumgartner (eds.), Hamburg: Meiner. − (1979)	"Von	der	psychologischen	Analyse	der	Tonqualitäten	in	ihre	eigentlich	ersten Elemente", in Brentano, Untersuchungen zur Sinnespsychologie, Meiner: Hamburg 1979),	p.	93-103. − (1929a) "Über die Gründe der Entmutigung auf philosophischem Gebiet", in O. Kraus,	(ed.),	Über	die	Zukunft	der	Philosophie:	nebst	den	Vorträgen,	Hamburg:	Meiner, p.	82-100. − (1929b) « Die Habilitationsthesen », in Kraus, Oskar (ed.), Über die Zukunft der Philosophie, Hamburg: Meiner, p. 133-141. − (1929c) "Über	die	Zukunft	der	Philosophie", in	O.	Kraus (ed.),	Über	die	Zukunft	der Philosophie,	Hamburg:	Meiner,	p.	1-48. − (1929d) "Über Schellings Philosophie", in O. Kraus (ed.), Über die Zukunft der Philosophie,	Hamburg:	Meiner,	p.	103-132. − (1907)	Untersuchungen	zur	Sinnespsychologie,	Leipzig:	Duncker	&	Humblot. − (1893-1894) Lectures	: Zeitbewegende philosophische Fragen, Houghton Library	: Harvard,	LS	20, p.	29366-29475. − (1869) 'Auguste Comte und die positive Philosophie', Chilianeum, Blätter für katholische	Wissenschaft,	Kunst	und	Leben	2	(1869),	15-37;	new	edition	by	O.	Kraus, (ed.),	Die	vier	Phasen	der	Philosophie	und	ihr	augenblicklicher	Stand,	Hamburg:	Felix Meiner,1968, p.	97-133. Crane,	T.	(2014)	Aspects	of	Psychologism,	Cambridge:	Harvard	University	Press. Fisette,	D.	(2015)	«	Husserl	et	Mach.	La	phénoménologie,	le	phénoménisme	et	la	querelle	du psychologisme	»,	M.	Geymant	(dir.)	Psychologie	et	psychologisme,	Paris,	Vrin,	p.	135-164. − (2014a) «	Franz Brentano et le positivisme d'Auguste Comte	», Cahiers philosophiques	de	Strasbourg, vol.	35,	no.	1,	2014,	p.	85-128. − (2014b) «	Austrian Philosophy and its Institutions: Remarks on the Philosophical Society	of	the	University	of	Vienna	(1888–1938)	»,	Philosophical	papers	dedicated	to Kevin	Mulligan,	A.	Reboul	(ed.),	Berlin	:	Springer,	p.	349-374. Husserl, E. (1994) Briefwechsel. Die Brentanoschule, Schuhmann Karl (ed.) Dordrecht: Kluwer,	vol.	I. Kirchhoff,	G.	R.	(1877)	Vorlesungen	über	Mechanik,	2.	ed.,	Leipzig:	Teubner. Mach,	E. − (1976)	Mach,	E.	Erkenntnis	und	Irrtum.	Skizzen	zur	Psychologie	der	Forschung, Leipzig:	Barth,	1905;	eng.	transl.	Knowledge	and	Error,	Dordrecht:	Kluwer. − (1943)	«	The	Economical	Nature	of	Physical	Inquiry	»,	Popular	Scientific	Lectures,	La Salle	:	Open	Court,	p.	186-213. − (1919)	Die	Mechanik	in	ihrer	Entwickelung	historisch-kritisch	dargestellt,	4th	ed., Leipzig:	Brockhaus,	1901;	The	Science	of	Mechanics,	transl.	T.	McCormack,	London: Open	Court,	1919. − (1914)	Analyse	der	Empfindungen	und	das	Verhältnis	des	Physischen	zum Psychischen,	6e	ed.,	Darmstadt:	Wissenschaftliche	Buchgesellschaft,	1991;	The Analysis	of	Sensations,	transl.	C.	Williams,	London:	Open	Court,	1914. − (1903)	Mach,	E.	"Über	das	Prinzip	der	Vergleichung	in	der	Physik,"	in Populärwissenschaftliche	Vorlesungen,	Leipzig:	Barth,	3rd	ed.,	p.	266-289. − (1883) Die Mechanik in ihrer Entwickelung historisch-kritisch dargestellt, Leipzig: Brockhaus. − (1891)"Sensations	and	the	Elements	of	Reality",	The	Monist,	Vol.	1,	p.	393-400. − (1892)	"Facts	and	Mental	Symbols",	The	Monist,	Vol.	2,	p.	198-208. Mill,	J.	S. − (1972)	The	Collected	Works	of	John	Stuart	Mill.	The	Later	Letters	of	John	Stuart	Mill, 1849-1873,	M.	Francis	and	L.	Dwight	N.	(eds.),	Toronto:	University	of	Toronto	Press, 1972,	vol.	XVII,	part	IV. − (1969) Auguste Comte and Positivism, 1865, in J. S. Mill, Collected Works of John Stuart	Mill,	vol.	X,	p.	261-36,	J.	M.	Robson	(ed.),	Toronto:	University	of	Toronto	Press, 1969. − (1865) An examination of Sir William Hamilton's philosophy, and of the principal philosophical	questions	discussed	in	his	writings,	London:	Longman,	Green,	Longman, Roberts	&	Green. Münch,	D.	(1989)	«	Brentano	and	Comte	»,	Grazer	Philosophische	Studien,	vol.	35,	p.	33-54. Neurath,	O. (1935)	Le	développement	du	Cercle	de	Vienne	et	l'avenir	de	l'empirisme	logique, Paris:	Hermann. Stadler,	F.	(1997)	Studien	zum	Wiener	Kreis,	Frankfurt:	Suhrkamp.