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Any attempt to analyze Nigeria’s national oil company (NOC), the Nigerian National Petroleum Corporation (NNPC), must first confront the question of what it really is. Despite its formal organization as a vertically integrated oil company, NNPC is neither a real commercial entity nor a meaningful oil operator. It lacks control over the revenue it generates and thus is unable to set its own strategy. It relies on other firms to perform essentially all the most complex functions that are hallmarks of operating oil companies. Yet unlike some NOCs it also fails to fit the profile of a government agency: its portfolio of activities is too diverse, incoherent, and beyond the reach of government control for it to function as a government policymaking instrument.
Nigeria depends heavily on oil and gas. Hydrocarbon activities provide around 65 percent of total government revenue and 95 percent of export revenues (Nigerian Ministry of Finance and Budget Office of the Federation 2008; EIA 2010a). While Nigeria supplies some LNG to world markets and is starting to export a small amount of gas to Ghana via pipeline, the great majority of the country’s hydrocarbon earnings come from oil. In 2008, Nigeria was the fifth-largest oil exporter and tenth-largest holder of proved oil reserves in the world (EIA 2010b).
Coronary artery atherosclerosis is the leading cause of death in the United States. Restenosis following percutaneous transluminal balloon angioplasty (PTCA) remains the limiting factor in the use of this treatment for coronary artery disease. Restenosis occurs in 30% of patients within 6 months. The restenotic lesion is a fibroproliferative response with resulting smooth muscle cell migration, proliferation and extracellular matrix production. Despite a decade of research there is no effective strategy for preventing restenosis in man.
Contemporary philosophy is indebted to Peter Unger for reviving the Sorites paradox. Unger argues that few, if any, of the things in our standard ontology really exist. Unfortunately, his arguments have not been taken seriously enough. I suspect that this is because he has been given too extreme an interpretation by some and too trivial an interpretation by others. In proclaiming himself a nihilist, he gives the impression that he believes that nothing exists – all of reality comes to nothing. It would seem that anyone who holds this position is too divorced from perception and reason to be taken seriously. But the Sorites paradox need not commit anyone to this extreme a nihilism. Even Unger is prepared to admit that something exists, but he thinks that in order to find out what that something is, and in order to be able to talk about that which exists in any detail, we must go through a fundamental conceptual change. He asserts that he is not prepared to offer any workable alternative conceptualization, but he does not claim that there could not be one.
On the other hand, Sorites arguments can instead be understood as being relevant only to language and not to reality. It may be admitted that the words ‘heap’ and ‘stone’ and ‘person’ do not apply to anything because of their vagueness. Yet this fact should not lead us to doubt the existence of the things that we had thought we could refer to with the words ‘heap’, ‘stone’, and ‘person’.
I have argued that the standard ontology is false and should be replaced by the hunk ontology. Of the four alternative ways to handle vagueness, three of them were unacceptable. However, the alternative that I end up accepting is likely to seem far more extreme than the three that I rejected. My goal in this chapter is to eliminate some of the feeling of extremism associated with the rejection of the standard ontology. One approach, common in contemporary philosophy, would be to present a paraphrase. In this case I would not have to reject the standard ontology so much as redescribe it. The goal would be to interpret our everyday utterances in a way that commits their users only to the objects of the true ontology. If done correctly, those everyday sentences that seem to be true will in fact be true once they are paraphrased, and those that seem to be false will in fact be false once they are paraphrased.
There are some questions as to what follows from our ability or inability to produce an adequate paraphrase. If the paraphrase project can be completed, does that show that we have been talking about hunks all along, or does it only show that our old false nonhunk talk can be replaced by our new true hunk talk? If the latter, why is this valuable? Is it because it presents a means for getting us to start saying true things, or because it provides an explanation of why it is not so bad for us to keep saying false things?
Coincident entities, if there were such things, would be distinct objects occupying exactly the same space at exactly the same time. The most difficult examples of coincident entities to explain away are those in which the two objects in question exist for exactly the same time and in exactly the same space for all the time that they exist, but differ in their modal properties. Consider two lumps of clay, one of which is shaped like the bottom half of a statue and the other like the top half of a statue. At the moment that those lumps are stuck together two distinct objects are brought into existence. One is a larger lump of clay composed of the two lumps. The other is a statue. When the original two lumps are again separated both the larger lump and the statue cease to exist. The larger lump and the statue are spatially and temporally coincident, but they are not identical. For instance, it is true of the lump that it could have had a completely different shape, but this is not true of the statue.
In spite of such very plausible examples, coincident entities would be very odd things. If there were any, they would have to have every spatial region in common at the time at which they were coincident. At that time, therefore, they would have exactly the same molecular substructure.
The ontology of physical objects I will defend in this work is that of four-dimensional hunks of matter. Some of these hunks are temporal parts of others. Thus, I place myself in the same general camp as Willard Van Orman Quine, John Perry, and David Lewis. Lewis mentions a common objection to such an ontology, and begins to answer it:
Some would protest that they do not know what I mean by “more or less momentary person-stages, or time-slices of continuant persons, or persons-at-times.” … [This] objection is easy to answer, especially in the case where the stages are less momentary rather than more. Let me consider that case only, though I think that instantaneous stages also are unprob-lematic; I do not really need them. A person-stage is a physical object, just as a person is. (If persons had a ghostly part as well, so would person-stages.) It does many of the same things that a person does: it talks and walks and thinks, it has beliefs and desires, it has a size and shape and location. It even has a temporal duration. But only a brief one, for it does not last long. (We can pass over the question how long it can last before it is a segment rather than a stage, for that question raises no objection of principle.) It begins to exist abruptly, and it abruptly ceases to exist soon after. […]
This provocative book attempts to resolve traditional problems of identity over time. It seeks to answer such questions as 'How is it that an object can survive change?' and 'How much change can an object undergo without being destroyed'? To answer these questions Professor Heller presents a theory about the nature of physical objects and about the relationship between our language and the physical world. According to his theory, the only actually existing physical entities are what the author calls 'hunks', four-dimensional objects extending across time and space. This is a major contribution to ontological debate and will be essential reading for all philosophers concerned with metaphysics.
This text is devoted to developing an ontology of four-dimensional hunks of matter. I argue that every filled region of spacetime is exactly filled by one such object and that any one of these objects has its actual spatiotemporal configuration and location at every world at which it exists. This ontology should be contrasted with what I take to be our standard ontology, according to which one and the same three-dimensional object exists in its entirety at several times and at several worlds, having a different spatiotemporal shape and location at many of these other worlds. My arguments can be taken to support either of the following conclusions: (A) the standard ontology should be rejected and the hunk ontology accepted; (B) the standard ontology must really be the hunk ontology rather than the ontology of three-dimensional objects that exist at worlds at which they have different configurations and locations. For the most part I present my arguments as a defense of (A), but I will also show how to read them as a defense of (B).
Since I hope to argue for the hunk ontology over the “standard ontology,” it is natural that this book should contain both a constructive project and a destructive project, though it is crucial that the two projects not be completely separated. Much of the constructive project is closely connected to the work of David Lewis and much of the destructive project is closely connected to the work of Peter Unger.