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This chapter presents Armstrong’s last paper on philosophy of mind, where he recounts the origins of David Lewis’s seminal paper ‘An Argument for the Identity Theory’ which appeared in 1966, two years before Armstrong’s book. Armstrong situates Lewis’s theory in relation to his own theory and in so doing adds an important seam to the familiar narrative of how the causal theory of mind emerged in the years immediately after the publication of A Materialist Theory of the Mind. The historiography, created and propagated by Armstrong himself, has always rightly emphasized the priority of U. T. Place and J. J. C. Smart, but until now there has not been such a detailed account from Armstrong himself of Lewis’s ‘causal role’ in the first wave of thinking about the mind.

The vertebrate fauna of the Sir Joseph Banks Group includes 6 native (2 now extinct) and 7 introduced mammals, 76 native and 4 introduced birds and 15 native and 1 introduced reptile. The determination of the total mammal fauna includes examination of sub-fossil bone collections from both Reevesby and Spilsby Islands. Tammar wallaby, bush rat and greater stick-nest rats were only recorded from sub-fossils, but the successful reintroduction of the stick-nest rat to Reevesby Island begun in 1990, is described. Two species of bat are recorded from the two large islands, Spilsby and Reevesby. An Australian sea lion haul-out site on Blyth Island is described for the first time. Counts of the number of pairs of Cape Barren geese now breeding on Spilsby Island are also published here for the first time. The islands of the Sir Joseph Banks Group are very significant for the conservation of species with large and important breeding populations there such as Cape Barren geese, black-faced cormorants, white-...

Although the snow leopard (Uncia uncia) is a common endangered felid species in zoos, little is known about the complex endocrine interactions controlling ovarian function and conception in this species. The goal of this work was to characterize ovarian activity throughout the estrous cycle, nonpregnant luteal phase (pseudopregnancy), and gestation in female snow leopards. This goal was accomplished using an enzyme immunoassay to measure fecal concentrations of estrogen metabolites (E) and progesterone metabolites (P). Fecal samples were collected from 12 female snow leopards (ages 18 months to 18 years) during one to three breeding seasons. In each breeding season, the majority of females (78%, 88%, and 100%, respectively) began to exhibit ovarian activity in December or January. The estrous cycle, defined by the first day of estrus (E ≥ 2 × basal concentration) to the first day of the subsequent estrus, was 12.7 ± 0.6 days (n = 145 cycles). Estrus lasted 4.3 ± 0.4 days with mean concentrations of fecal E during the follicular phase (1661 ± 139 ng/g feces) increasing 3.2-fold above basal concentrations (515 ± 32 ng/g feces). No spontaneous ovulations were observed in any of the cycling females. Nonpregnant luteal phases were observed in eight females that bred but did not become pregnant. The length of the nonpregnant luteal phase ranged from 11 to 72 days (45.7 ± 5.7 days; n = 10) with mean concentrations of fecal P during the luteal phase (12.46 ± 1.7 μg/g feces) increasing 6.2-fold above basal concentrations of P (2.01 ± 0.2 μg/g feces). Three of the females in the study became pregnant and gave birth after a gestation of 93 (n = 2) and 95 (n = 1) days. Fecal P concentrations during pregnancy increased to 11.64 ± 1.3 μg/g feces, or 5.8-fold above basal concentrations. The results of this study provide a comprehensive characterization of reproductive endocrinology in snow leopards, and confirm that fecal hormone monitoring is an effective way to monitor female snow leopards throughout the breeding season.

First published in 1985, D. M. Armstrong's original work on what laws of nature are has continued to be influential in the areas of metaphysics and philosophy of science. Presenting a definitive attack on the sceptical Humean view, that laws are no more than a regularity of coincidence between stances of properties, Armstrong establishes his own theory and defends it concisely and systematically against objections. Presented in a fresh twenty-first-century series livery, and including a specially commissioned preface written by Marc Lange, illuminating its continuing importance and relevance to philosophical enquiry, this influential work is available for a new generation of readers.

Preliminary The strength of the case against the Naive Regularity theory of laws in particular, and the Regularity theory of laws in general, should now be evident. Some of the difficulties which have been rehearsed have been appreciated by Regularity theorists themselves. It is rather generally recognized that the class of Humean uniformities includes members which we do not wish to include among the laws of nature. A number of Regularity theorists have also recognized that it is not even easy to say what a uniformity is. The trouble here is provided by strange predicates such as ‘grue’. Suppose that all Fs are Gs, but that the predicates ‘F’ and ‘G’ pick out what we would naturally think of as a heterogeneous miscellany. Is this a Humean uniformity? Intuitively, no. But the unsupplemented Naive Regularity theory seems to lack the resources to eliminate such ‘uniformities’. More recently, Regularity theorists have faced up to the difficulties posed for their view by the apparent existence in nature of irreducibly probabilistic laws. There is no simple emendation of the Naive theory available for dealing with such laws. For instance, it is no good substituting relative frequencies for uniformities, because certain relative frequencies are only the most probable , not the inevitable, manifestations of probabilistic laws. The only way to preserve a Regularity theory seems to be to introduce objective single-case chances or propensities, and then assert that probabilistic laws are uniformities linking more ordinary properties with these new sorts of property. Against this background, let us consider various attempts to produce sophisticated versions of the Regularity theory. (For an account of the earlier literature, see Suchting, 1974.) The attempts fall under two heads in the first place. First, there are those who look for an external criterion to mark off ‘good’ from ‘bad’ uniformities. The criterion given is always, in a broad sense, epistemic. It is a matter of our cognitive attitudes to the uniformities – what evidence we have for them, and so forth. Second, there are those who look for an internal criterion, something about the uniformities themselves. There are, in turn, two types of view here. First, there is Brian Skyrms’ recent attempt (1980) to mark off the good uniformities as the resilient ones.

Pied tamarins are an endangered Amazonian primate that has limited breeding success in zoos. Unfortunately, little is known about their reproductive biology and adrenocortical activity. Objectives were: (1) determine if fecal hormones could be utilized to monitor gonadal and adrenocortical activity; (2) characterize male and female gonadal and adrenocortical hormones; and (3) determine if there were differences between adrenocortical activity and behavior in a nonbreeding, on-exhibit (NB-ON) pair compared to a breeding, off-exhibit (B-OFF) pair. Fecal samples were collected from four (two males; two females) individuals. Hormones were analyzed for fecal progesterone (FPM), androgen (FAM), and glucocorticoid (FGM) metabolites by enzyme immunoassay. Behavioral observations were conducted for 6 months. Data were collected on instantaneous behavior, location, and all occurrences of intraspecific behaviors. Fecal progesterone metabolites were validated by pregnancy (mean ± SE, pregnant: 28.47 ± 1.60 μg/g; nonpregnant: 8.63 ± 0.89 μg/g). Fecal androgen metabolites were higher (T = 31,971, P < 0.05) in the B-OFF male (863.66 ± 46.30 μg/g) than the NB-ON male (838.63 ± 60.70 μg/g). Fecal glucocorticoid metabolites were validated by response to veterinary procedure with elevated values (7.31 ± 1.48 μg/g) seven times the baseline (0.37 ± 0.04 μg/g) at 24-hr postphysical. Females had higher baseline FGM than the males (P < 0.05). Baseline FGM were higher (P < 0.05) in the NB-ON female (0.93 ± 0.03 μg/g) compared to the B-OFF female (0.38 ± 0.02 μg/g). Similarly, the NB-ON male's FGM baseline (0.71 ± 0.03 μg/g) were higher (P < 0.05) than the B-OFF male (0.21 ± 0.01 μg/g). Behavioral data revealed stereotypical behaviors in the NB-ON pair but no stereotypical behaviors in the B-OFF pair. Fecal hormone monitoring and behavioral analysis may provide insight on the limited breeding success of pied tamarins in zoos.

Dans le cadre de la theorie des marqueurs de verite (truthmaker), l'A. etudie les cas difficiles ou l'on peut douter de leur necessite: il s'agit des verites negatives, des verites generales et des verites modales. Au-dela du «Tractacus» de Wittgenstein et au-dela de «L'Atomisme logique» de Russell, l'A. refute l'idee que les verites necessaires ont des proprietes positives, simples et particulieres en relation avec le monde, et admet la possibilite de la contingence comme marqueur de verite minimal.

The cortico-nuclear (C-N) and nucleo-cortical (N-C) projections of the C1 cortical zone in pars anterior (pa) and pars copularis (pc) of the paramedian lobule (PML) in the posterior lobe of the cat cerebellum were investigated with a combined electrophysiological and neuroanatomical technique. In each experiment the mediolateral boundaries of the zone were located on the cortical surface by recording field potentials mediated via climbing fibres and evoked in the zone by activity elicited in spino-olivocerebellar paths through percutaneous stimulation of fore- and hindlimbs; a small (15-30 nl) injection of WGA-HRP was then made into the zone. The distributions in the deep cerebellar nuclei were determined (with light microscopy) both for terminal labelling due to anterograde axonal transport by Purkinje cells and for cell bodies labelled due to retrograde transport in N-C axons. The extent to which injection sites were confined to the C1 zone was assessed both by comparing injection site and zone widths and by determining the distributions of retrogradely labelled neurones within the contralateral inferior olive. The C-N projection from the part of the zone in PML pa (a forelimb part) terminates almost exclusively (perhaps exclusively) in nucleus interpositus anterior (NIA), primarily in caudal and dorsal parts, where it overlaps heavily with the C-N projections from the lobule V parts (also forelimb parts) of the C1 and C3 zones as previously defined. The C-N projection from the part of the zone in PML pc (a hindlimb part) also terminates virtually exclusively in NIA but primarily in almost all parts of the medial third of the nucleus. There is, nevertheless, sufficient overlap between the PML pa and PML pc projections that approximately one third of the termination territory of each projection overlaps that of the other. The PML pc part of the zone is almost entirely lacking in a N-C projection, as previously found for the lobule V part of the C1 zone (and C3 zone). However, the PML pa part of the zone receives N-C projections that arise, in descending order of size, from nucleus interpositus posterior (NIP), from NIA, from the NIA/nucleus lateralis (NL) fusion area and (perhaps) NL. The projection from NIP is similar in size to that provided by the nucleus to the C2 zone in lobule V of the anterior lobe. The findings are discussed, with particular emphasis on their implications for the hypothesis that the cerebellum is divisible into a number of olivo-cortico-nuclear complexes or compartments.

1. The discharge patterns of 166 lateral cerebellar neurones were studied in cats at rest and during visually guided stepping on a horizontal circular ladder. A hundred and twelve cells were tested against one or both of two visual stimuli: a brief full-field flash of light delivered during eating or rest, and a rung which moved up as the cat approached. Forty-five cells (40%) gave a short latency response to one or both of these stimuli. These visually responsive neurones were found in hemispheral cortex (rather than paravermal) and the lateral cerebellar nucleus (rather than nucleus interpositus). 2. Thirty-seven cells (of 103 tested, 36%) responded to flash. The cortical visual response (mean onset latency 38 ms) was usually an increase in Purkinje cell discharge rate, of around 50 impulses s-1 and representing 1 or 2 additional spikes per trial (1.6 on average). The nuclear response to flash (mean onset latency 27 ms) was usually an increased discharge rate which was shorter lived and converted rapidly to a depression of discharge or return to control levels, so that there were on average only an additional 0.6 spikes per trial. A straightforward explanation of the difference between the cortical and nuclear response would be that the increased inhibitory Purkinje cell output cuts short the nuclear response. 3. A higher proportion of cells responded to rung movement, sixteen of twenty-five tested (64%). Again most responded with increased discharge, which had longer latency than the flash response (first change in dentate output ca 60 ms after start of movement) and longer duration. Peak frequency changes were twice the size of those in response to flash, at 100 impulses s-1 on average and additional spikes per trial were correspondingly 3-4 times higher. Both cortical and nuclear responses were context dependent, being larger when the rung moved when the cat was closer than further away. 4. A quarter of cells (20 of 84 tested, 24%) modulated their activity in advance of saccades, increasing their discharge rate. Four-fifths of these were non-reciprocally directionally selective. Saccade-related neurones were usually susceptible to other influences, i.e. their activity was not wholly explicable in terms of saccade parameters. 5. Substantial numbers of visually responsive neurones also discharged in relation to stepping movements while other visually responsive neurones discharged in advance of saccadic eye movements. And more than half the cells tested were active in relation both to eye movements and to stepping movements. These combinations of properties qualify even individual cerebellar neurones to participate in the co-ordination of visually guided eye and limb movements.

Immunocytochemical techniques were employed to examine the changes in the GABA receptor subunits beta2/3 within the dentate gyrus of the rat brain 1, 3, 7, 14, 30 and 90 days after a unilateral perforant pathway lesion. Three days post-lesion we observed a decrease in beta2/3 immunolabeling in the inner molecular layer of the dentate gyrus followed by a comparable decrease in the outer molecular layer 7 days post-lesion. These decreases were transient; 30 and 90 days post-lesion, beta2/3 immunolabeling appeared similar to controls in the inner portion of the molecular layer, while in the outer region the labeling was increased. In this latter region we also observed a dense band of AChE fibers. Following survival times of 3 days we observed a diffuse staining of the neuropil in the hilar region, and a dense amorphous accumulation of peroxidase reaction product in the polymorphic region. These responses were transient and by 14 days the hilar/polymorphic region appeared indistinguishable from controls. These data suggest a unique pattern of immunoabeling in the molecular and polymorphic region in response to perforant pathway lesion. A putative explanation for this response is discussed.