Colonial Temper

In the context of the recent Indian Science Congress, it is pertinent to take up the issue of "scientific temper". A frequent lament is the lack of "scientific temper" in India, as articulated in a typical recent article by Ravi Sinha,[1] a former scientist.

At the outset let me clearly say: I am all for doing things in a (truly) scientific way. I add the term “truly” to emphasize that being scientific does not mean blindly imitating whatever the current scientific community does.

Thus, from an early stage of colonialism in India, science got inextricably mixed up with a psyop,  a political project of colonial domination. Most famously, Macaulay[2] (a Whig historian, whom Marx rightly called a “falsifier of history”[3]) asserted that the West is “immeasurably superior” in science, and hence must be imitated. Macaulay used that claim of Western superiority in science to change our education system. That changed education system could not be unchanged even after independence, and persists to this day. It inculcated in the colonised a deep-seated desire to slavishly imitate the “superior” West, as is manifest in so many ways. Nevertheless, the colonised, including Marxists, never considered the possibility that Macaulay tricked them by using a false history of science, to assert Western superiority. They never tried to cross-check it, and refuse to do so today!

Therefore, for an adequate discussion of scientific temper, we first need a new term “colonial temper”, with which scientific temper is often confounded because of the colonial project of psychological domination. Colonial temper is characterized by the use of false narratives to generate (1) a belief that the West is “superior” and must be imitated in all matters, especially in mathematics and science, followed by (2) an extreme and uncritical adulation of the West, AND repeated assertions of the non-Western inferiority.

The colonial teaching of Western “superiority” entails the “trust the West” syndrome: that only the colonizer is to be trusted, and everyone else distrusted. This claim was central to colonialism or con-all-ism. Obviously, to con the colonised, and get them to believe the colonial narrative, it was first necessary to gain their trust. Today, this claim of “Western trustworthiness” is heavily used by Wikipedia which “educates” the world, but is premised on the belief that ONLY Western (or Western-approved) secondary or tertiary sources are “reliable” and to be trusted. Once one accepts that, everything else (including blind imitation of the West) follows.

That is, this claim of Western superiority, and inferiority of the colonised, instilled by colonial education, had the obvious political consequence of making the colonized mentally subservient to the colonizer: the resulting political advantage continues long after political independence (which should hence not be confounded with the end of colonialism).

As explained elsewhere,[4] and elaborated below, the claim of Western superiority (used to justify colonialism) is a direct outcome (a mutation) of the earlier claims of (1) White superiority (used to justify slavery), and (2) the still earlier claim of Christian superiority (used to justify both genocide and slavery, and grab land in Americas and Australia). So, the immense political and economic benefits to the West of these earlier excessively stupid and immensely evil claims of superiority is obvious. (Recall that after the Christian church married the Roman state, in the 4th c., it abandoned its earlier belief in equity,[5] and its major dogma and propaganda plank became the assertion of Christian superiority combined with the assertion of the inferiority of others.)

So, the key question is this: are any of these claims of superiority true, or is the alleged absence of scientific temper in India just another propagandist weapon being used to assert the inferiority of the colonised in exactly the church tradition used by Macaulay? That talk of scientific temper is a political project, not a search for truth, is clear from the coarse lies that are told to support it. These lies are of two sorts (1) lies to run down the scientific achievements of the colonised, to declare them inferior, and (2) lies to hugely exaggerate the scientific achievements of the coloniser, to declare the coloniser superior and suppress the coloniser’s superstitions. Let us start with the type 1 lie.

Thus, Ravi Sinha sweepingly asserts, “scientific temper is largely missing from the societies and cultures that form a distinct civilisation on the subcontinent”. This colonial narrative of lack of scientific temper in India, at the civilizational level, is totally contrary to facts. To this end, let us first see five examples of “scientific temper” in India.

Scientific temper in India: five examples

1. Experimental method in ancient India
Thus, for example, the experimental method is a key aspect of science, and the first recorded systematic use of the experimental method is in India by Payasi.[6] This is NOT an isolated feature peculiar to the Lokayata in India: every traditional system of Indian philosophy, without exception, accepts the empirically manifest (prtayaksh) as the first (hence most important) means of proof.[7] Consequently, down the ages, numerous Indians stood up against superstitions, whereas numerous people in the West succumbed to church superstitions for centuries, because the church which ruled the West asserted the testimony of the Bible (authority, shabd praman) as the first means of proof.

Because the aim is to assert the inferiority of the non-West, for political reasons, the West will stick to its false history of science and refuse to correct it: they refuse to acknowledge even the existence of Payasi. Thus, Payasi was thousands of years before Francis Bacon, to whom the West falsely continues to attribute the origin of the experimental method, even decades after the case of Payasi is pointed out. Also, it is never acknowledged that Bacon was deeply superstitious for he asserted that "the word of God [Bible] ...[is] the surest medicine against superstition"![8] Why shouldn’t the non-Westerners make Bacon an example to howl with laughter for eternity about the inferiority of the West and its lack of scientific temper?

2. Astronomy vs astrology: Jyotish as timekeeping

Of course, Indians had science from long before Payasi, right since the earliest recorded time of the Veda-s. Thus, Vedic yajna-s stipulate precise timing, and the Vedanga Jyotisha[9] is entirely a scientific manual of time reckoning by the stars or the science of astronomy. The available recension of this Vedanga text is unambiguously dated between −1400 CE and −1900 CE using the astronomical observations it mentions (which observations were first rejected as dated by the 6th c. Varahamihira).

But admitting the scientific nature of this early text is anathema to false Western pride, hence the colonised choose to just brazenly lie that jyotisha means astrology. Alienated from their culture, some don’t see that there is a separate term for astrology (=phalit jyotish), whereas, as stated in Yajush Vedanga jyotish verse 3, jyotish means “kala vidhan shastram” or the science of timekeeping.

I have repeatedly and very publicly challenged[10] people over the last 20 years to point out even a single sentence on astrology in the Vedang Jyotisha, which is entirely a manual on timekeeping. No one met this challenge but facts are irrelevant for purposes of propaganda that Indians lacked scientific temper. Hence the colonised stick to the lie of conflating jyotish with phalit jyotish. Actually, the Indian astronomy was not only a science, its level of precision in time of the Vedanga Jyotish is clear from the use of the term “bhamsha” about 0.1 degree (360 degrees = 3348 bhamshas[11]).

On the other hand, thousands of years later, prominent Western astronomers were astrologers: Kepler not only obtained a livelihood by casting horoscopes, he laughably wrote that it was divine harmony that his god had provided astrology as a means of livelihood to astronomers![12] But because the propagandist aim is to glorify the West, Kepler’s superstitions are suppressed, and few are aware of them.

It is another matter that the near-blind Kepler’s “observations”, which he later dishonestly fudged,[13] came from a manuscript which his master Tycho Brahe kept secret even from him, obviously because of its heretical (foreign) origins at this time of the Inquisition. Kepler ran away with that manuscript after Tycho’s death (or murder by Kepler[14]), also grabbing Tycho’s lucrative job. Tycho’s masonry instruments (copied from Ulugh Beg’s) were crude, and incapable of precise measurement, and it is not hard to judge Tycho’s secret manuscript sources of “observation” given that the “Tychonic” planetary model is a carbon copy of Nilakantha’s earlier planetary model.

But admitting that Indians had sophisticated astronomy and planetary models prior to colonialism, would destroy Macaulay’s propagandist narrative of oriental “Astronomy, which would move laughter in girls at an English boarding school”. How much would those “girls (sic)” be moved to laughter when they learn that the top Western astronomer then could do nothing better than steal from and imitate Indian astronomy?

As the Royal Astronomer to the Holy Roman Empire, Tycho was the natural recipient of astronomy texts stolen from India (Cochin) by Jesuits in the 16^th c.[15] On the doctrine of Christian discovery used to grab all land in the Americas, all this knowledge is deemed to “belong” to Tycho, since he was the “first Christian discoverer” of this knowledge. It is not hard to understand why European astronomy made little progress before the opportunity for theft of knowledge. But we already know the response of the votaries of “scientific temper”, simply deny the facts and stick to Macaulay’s narrative for its political benefits.

3. The scientific theory of eclipses in India
Again, colonised historians keep on repeating that Indians are superstitious, because, for example, they believed in Rahu-Ketu. These historians are too dishonest to even once acknowledge how Rahu and Ketu were used as scientific terms for lunar nodes, needed for any scientific theory of eclipses, a theory which long existed in India, at least since the 3rd c. Surya Siddhanta.

Briefly, an eclipse requires that the moon should be in or near the plane of the ecliptic, which happens at the two lunar nodes, or points at which the moon’s orbit intersects the ecliptic. The scientific terms for those two nodes were Rahu and Ketu. So, the fact is Indians did have a valid scientific theory of eclipses, and the desi calendar still predicts the eclipses using that theory.



The colonial falsehood about Rahu-Ketu is as crude a falsehood as it would be to say that current Western geography is superstitious because it uses the mythological term Atlas (on whose shoulders the earth was thought to rest in Greek mythology), or that modern star charts are proof of Western superstition since they similarly involve nomenclature from mythology, such as Orion (on Greeks mythology that dead souls turn into stars). But expect only double standards from colonised propagandists.

Incidentally, because early Greeks and Romans were a superstitious lot, there is no record of any early Greek ever refuting that myth of Atlas, still celebrated in modern times by authors like Ayn Rand, But in India this was refuted, using common sense, by Lalla:[16]

(20.41) If the earth is supported by a tortoise or other things, by whom are they supported in space? If they can remain in space [unsupported] what prevents the earth from remaining thus [unsupported]?

Vatesvara[17] gives a sophisticated reason why the earth cannot fall.

(V.3) If you are inclined to believe that it falls down, say what is up and down for an object standing in space. The globe of the Earth...in what direction should it then fall?

He goes on to explain that things fall towards the centre of spherical earth.

(V.7) As here in our locality a flame of fire goes aloft in the sky and a heavy mass falls towards the Earth, so is the case in every locality around the Earth. As there does not exist a lower surface (for the Earth to fall upon), where should it fall?

But this according to Ravi Sinha is described as civilisational lack of scientific temper in India, whereas “Atlas” is scientific since used in Western geography!

Also, a fact that colonial historians will never honestly admit: the demonic theory of eclipses was explicitly denied for centuries by numerous Indians,[18] specifically on the grounds that the time of eclipses could be calculated, and that different parts of the sun or moon were seen to be eclipsed in different places etc.

Thus, Lalla,[19] in his chp, 18 on “Correcting mythical knowledge” says

22. If you are of the opinion that an artful demon is always the cause of an eclipse by swallowing (the Sun or Moon), then how is it that an eclipse can be determined by means of calculation? Moreover, why is there not an eclipse on a day other than the day of New or Full Moon.

25. An eclipse cannot be caused by Rahu [swallowing the Moon, Sun], because the sides of the discs of the Sun and Moon, which are first to be eclipsed, are not the same; nor are the portions eclipsed the same; and nor even are the durations the same.

26. In a solar eclipse, people at different part (of the earth) see different portions of the Sun eclipsed. Some do not see (the eclipse) at all. Knowing this, who can maintain that an eclipse is caused by Rahu?

But those with colonial temper only learnt how to memorize and recite abject colonial lies about Indian inferiority, and the facts be damned. Mistranslating/misrepresenting one word (jyotisha, Rahu, curse of Ham) is usually enough to fool the mass of Western nitwits who for centuries believed their white skin makes them superior.

Worse, at the same time when Indians were explicitly denying the demonic theory of eclipses, the 5^th c. Bible asserted a divine theory of eclipses by speaking of darkness at noon[20] (or a solar eclipse) to show the Christian god’s anger at the crucifixion of Christ. Fine example of Western scientific temper? No! This is an absurd superstition because the date of Easter (or the purported resurrection of Christ) on the Christian calendar (our current calendar) was fixed for Sunday after a full moon,[21] at which time a solar eclipse is impossible. (The sun and moon should both be on the same side of the earth for a solar eclipse, not on opposite sides as happens at full moon.) Laughably, the superstitious West did not understand it, but regarded it as gospel truth.

But for colonial historians it is taboo to ever admit that the West was steeped in superstitions at a time when the non-West was scientific. Their aim is not an objective examination of facts to determine which societies had scientific temper, but to engage in pitiable falsehoods to somehow put down the non-West as inferior using the crudest of lies. The persistent use of falsehoods is proof of the propagandist intentions.

4. Indian knowledge of round earth: gola

Many similar examples can be given. Unlike the Bible which superstitiously speaks of a flat earth,[22] Indians had a scientific account of the round earth, incorporated in its very name. The 5th c. Aryabhata, contemporaneous with the Bible, most famously said the earth is round like a kadamba lower and stands supportless in space.[23]


Image (c) istock.com

His disciples (Lalla[24], Vatesvara[25]) explained that the roundness of earth is manifest from the observation that far off trees cannot be seen (and the horizon is round). Lalla says:

(20.35) Mathematicians say that one hundredth of the circumference of the earth appears to be plane.

(20.36) If the earth is level, why cannot tall trees like the date palm, alas, be seen by man, when at a very great distance from the observer.

The West under the tutelage of the church went by the authority of the Bible, not observations. So who had scientific temper?

Indeed, this observation, or measurement of the distance from here to the horizon, a navigational unit called the zam,[26] provided a way to measure earth’s size. And Indians did accurately calculate the earth’s radius using elementary trigonometry and the distance to the horizon. This was easily done by measuring the height h of a mountain (elementary trigonometry) and then measuring the dip of the horizon as described in my class IX school math text. This is explained in the figure; the rest, calculating the radius of the earth r from h and the observed value of the dip angle is again elementary trigonometry. (Note that Indians worked with angles as arc length[27] (=capa), so “angle of dip” is the arc-length or distance from the base of the hill to the horizon.) This is an easy experiment conducted by my students.[28]

As already stated, angles were being measured to a precision of 0.1 degrees from the times of the Vedanga Jyotish, and I have described a traditional navigational instrument the kamal[29] which has similar accuracy. Of course, in this case, more accurate time measures can also be used to measure angles. But all this is supposed civilisational lack of scientific temper according to Sinha.



Alas, the West (which supposedly had scientific temper) could not do that elementary stuff, it could NOT correctly determine the earth’s radius even a thousand year after Aryabhata. Why not? Just because the West was excessively superstitious (believed in the Biblical flat earth) AND also backward in math (hence science). The proof? As the 7th c. Brahmagupta succinctly stated[30]



which may be translated “ignorance of the earth radius makes longitude [calculations] futile”.

European backwardness (in elementary trigonometry), resulted in failure to determine earth’s radius accurately. Hence, Indian techniques of longitude determination, which involved the radius of the earth as a key parameter, could not be used by Europeans, even after stealing knowledge in precolonial times.[31] This resulted in the famous navigational problem of longitude determination peculiar to Europe. But the superstitious colonised, like gullible children, go only by the narratives they are told by the West; they never check facts. Then they preach to us, like Christian missionaries.

The European navigational problem was only half-solved by the West, even a 1000 years after Brahmagupta, by offering huge prizes, such as the British longitude prize legislated in 1712. Half the prize was given for Harrison’s chronometer in 1762 (since it was not sure the prize had been won). But that grand narrative of the chronometer neglects the fact that the actually available chronometers were faulty until the mid-19th c.

This fact of Western backwardness in the critical technology of navigation, due to its mathematical and scientific backwardness, even at the very time Macaulay was boasting of its “immeasurable superiority” is never to be admitted by colonial historians, because their aim is to lie and glorify the West. Even if someone did admit it, the church academic technique of secretive pre-publication review would ensure it is censored. If not it would be demonised by Wikipedia and others.

5. Aryabhata and motion of the earth

The bias of the votaries of scientific temper is again obvious as regards the motion of the earth. In the Western case, the narrative changes: it is again about one person, Galileo, who “heroically” denied a superstition (with the censor’s imprimatur!), but then succumbed to church pressure. Such narratives are enough for nitwit believers in White superiority. But we notice that the story is about one individual’s supposed heroism not about the persistence of the superstition for centuries before and after him. And where exactly is the heroism, given that Galileo succumbed to the pressure? Should the same norm of heroism be applied to all who succumbed to British torture (not pressure) during India’s struggle for independence?

Of course, as usual Indians were far more scientific. Some 11 centuries before Galileo, the lower caste[32] Aryabhata asserted the earth rotates[33] and that is the cause of the observed rotation of the celestial sphere in the reverse direction. Note that Aryabhata, though a dalit,[34] was socially confident enough to make such a radical claim, totally contrary to the stock propaganda of pre-colonial casteist oppression. But Aryabhata’s assertion ran into heavy weather. Many other Indians did oppose this. But there is no record of anyone opposing Aryabhata who opposed it on religious grounds, as happened in Galileo’s case, 11 centuries later. Presumably, this happened because of the purported lack of scientific temper in India because on the church/colonial narrative, the West purportedly (exclusively) had scientific temper, even though ruled by the church.

For example, Varahamihira’s opposition to Aryabhata’s claim of earth rotation was on scientific grounds, using exactly the two possibilities used by Fresnel and Stokes, and tested by the Michelson-Morley experiment,[35] 1400 years later. The two possibilities were that (1) the ether (=sky=akasa[36]) wind would stream past the earth, causing clothes on a clothes line to flap, or that (2) the ether near the earth would be dragged along, causing the falcon which flies high to lose it bearings.

But, as our so-called scientists keep telling us, the society which did not oppose Aryabhata on religious grounds is the one invariably painted as lacking scientific temper! That is a fraud and representative of the colonial temper of propaganda based on brazenly false narratives and denial of facts.

Summary and conclusions
The above five examples of scientific temper in India provide ample evidence that Indians have a long history of scientific temper from Vedic times right down to the advent of colonialism (which actually destroyed scientific temper in India as we will see).

The repeated claims to the contrary by people like Ravi Sinha are a deliberate falsehood, a fraud a la Macaulay, which avoids engaging with facts, and deliberately twists the meanings of words to peddle the same old colonial story of non-Western inferiority, to facilitate Western domination.

Continued to Next Page 
 

Footnotes:
[1] Ravi Sinha, ‘The Absence of Scientific Temper in the Lands of Bose, Raman and Salam’.
[2] T. B. Macaulay, ‘Minute on Education’, 1835.
[3] Karl Marx, Capital, chp. 27, footnote 1.
[4] C. K. Raju, ‘“Euclid” Must Fall: The “Pythagorean” “Theorem” and The Rant Of Racist and Civilizational Superiority — Part 1’, Arumaruka: Journal of Conversational Thinking 1, no. 1 (2021): 127–55,
[5] C. K. Raju, The Eleven Pictures of Time: The Physics, Philosophy and Politics of Time Beliefs (Sage, 2003).
[6] For a popular-level account see, C. K. Raju, ‘Did Indians Have Scientific Temper?’, ThePrint, India, 31 March 2019,  For the original sources, see Digha Nikaya, Payasi sutta. Hindi trans. Rahul Sankrityayan and Jagdish Kashyap, reprint Parammitra Prakashan, Delhi, 2002, pp. 199-201. Eng. trans. T. W. Rhys-Davids, Dialogues of the Buddha, vol. 2, London, 1910, pp. 346–74. Reprinted by the Pali Text Society, Sacred Books of the Buddhists, vol. 2, ed. F. Max Muller, Routledge and Keagan Paul, London, 1977. Reproduced in Cârvâka/Lokâyata: An Anthology of Source Materials and some Recent Studies, ed. Debiprasad Chattopadhyaya and Mrinal Kanti Gangopadhyaya, ICPR, New Delhi,1990, pp. 8–31.
[7] E.g. Satish Chandra Vidyabhushana, The Nyaya Sutras of Gotama (Allahabad: Panini Office, 1913) verse 2.
[8] Novum Organum, p. 89, The Works of Francis Bacon, ed. J. Spedding et al.,
[9] K. V. Sarma, ed., Vedanga Jyotisa of Lagadh, trans. Notes T. S. Kupanna Sastri (New Delhi: INSA, 1985).
[10] “Astrology in university education: twenty years after”, .
[11] K.D. Abhyankar, ‘On Two Important Provisions in Vedanga-Jyotisa’, Indian Journal of History of Science 37, no. 3 (2002): 213–22.
[12] J. Bruce Brackenridge and Mary Ann Rossi, ‘Johannes Kepler’s on the More Certain Fundamentals of Astrology Prague 1601’, Proceedings of the American Philosophical Society 123, no. 2 (1979): 85–116.
[13] William Donahue, ‘Kepler’s Fabricated Figures: Covering Up the Mess in the New Astronomy’’, Journal for the History of Astronomy 19 (1988): 217–37; William J. Broad, ‘After 400 Years, a Challenge to Kepler: He Fabricated Data, Scholars Say’’, New York Times C1 (23 January 1990): 6; ‘Planet Fakery Exposed. Falsified Data: Johannes Kepler’’, The Times (London, 25 January 1990, 31.
[14] Joshua Gilder and Anne-Lee Gilder, ‘Heavenly Intrigue: Johannes Kepler, Tycho Brahe, and the Murder Behind One of History’s Greatest Scientific Discoveries’ (New York: Dubleday, 2004).
[15] C. K. Raju, Cultural Foundations of Mathematics: The Nature of Mathematical Proof and the Transmission of Calculus from India to Europe in the 16th c, CE (Pearson Longman, 2007).
[16] Bina Chatterjee, trans., Sisyadhivrddihada Tantra of Lalla, 2 vols (Delhi: Indian National Science Academy, 1981).
[17] Kripa Shankar Shukla, Vatesvara-Siddhanta And Gola of Vaát­esvara (New Delhi: Indian National Science Academy, 1986).
[18] For a consolidated account, see “Indians against superstition”, extract from C. K. Raju, ‘Proofs and Refutations in Mathematics and Physics: An Indian Perspective’, in History of Science and Philosophy of Science, ed. P. K. Sengupta (New Delhi: Pearson Longman, 2012), 273–94. For the original sources, see Lalla, Sisyadhivrddihada, cited above chp. 20 (“Correction of mythical knowledge”), and Vatesvara, Gola,5.5, cited above.
[19] Chatterjee, Sisyadhivrddihada Tantra of Lalla.
[20] E.g. Luke 23:44.
[21] Raju, The Eleven Pictures of Time: The Physics, Philosophy and Politics of Time Beliefs.
[22] http://www.ckraju.net/hps-aiu/flat-earth-in-Bible.txt.
[23] Gola, 6-7, Aryabhatiya of Aryabhata, ed. K. S. Shukla and K. V. Sarma (Delhi: Indian National Science Academy, 1976).
http://ckraju.net/papers/presentations/images/Gola-6.jpg, 
http://ckraju.net/papers/presentations/images/Gola-7-Kadamba.png.
[24] Lalla, Sisyadhivrddihada.
[25] Shukla, Vatesvara-Siddhanta and Gola of Vatesvara.
[26] Raju, Cultural Foundations of Mathematics: The Nature of Mathematical Proof and the Transmission of Calculus from India to Europe in the 16th c, CE, p. The Arabic word zam derives from the Sanskrit yama, a very old unit of time measurement in India, also known as prahara, as in current do-pahara, or noon. This departs from the Indian sexagesimal system: a day+night is divided into 8 praharas=60 ghati-s. In the navigational context, later, this time unit changed into a unit of distance=the distance travelled in a prahara = 3 hours.
[27] C. K. Raju, Ganita vs Mathematics [Hindi]’, Himanjali 20, no. July-December (2020): 34–44.
[28] For the Indian method of determining the radius of the earth, and for an account of how my students did it, see above tweet.
[29] Raju, Cultural Foundations of Mathematics: The Nature of Mathematical Proof and the Transmission of Calculus from India to Europe in the 16th c, CE.
[30] Brahmagupta, Brahma-Sphuta Siddhanta, ed. Ram Swarup Sharma Sharma (New Delhi: Indian Institute of Astronomical and Sanskrit Research, 1966) chapter 11. verses 15-16.
[31] Raju, Cultural Foundations of Mathematics: The Nature of Mathematical Proof and the Transmission of Calculus from India to Europe in the 16th c, CE.
[32] C. K. Raju, ‘Aryabhata Dalit: His Philosophy of Ganita and Its Contemporary Applications”’, in Theory and Praxis: Reflections on the Colonization of Knowledge, ed. Murzban Jal and Jyoti Bawane (Routledge, London, 2020), 139–52,  C. K. Raju, ’Dalit uplabdhiyon ka jashn’, Jansatta, 30 September 2018, .
[33] Gola 9-10.Aryabhatiya of Aryabhata.
http://ckraju.net/papers/presentations/images/Gola-9-10-boat-analogy.jpg
[34] Raju, ‘Aryabhata Dalit: His Philosophy of Ganita and Its Contemporary Applications’.
[35] C. K. Raju, ‘Time: What Is It That It Can Be Measured?’, Science & Education 15, no. 6 (1 August 2006): 537–51, Draft at ckraju.net .
[36] C. K. Raju, Time: Towards a Consistent Theory (Kluwer Academic (Springer), 1994).