Idealism and Pragmatism: “Transcendent” Validity Claims in Habermas’s Democratic Theory

In her recent article “Realism and Idealism: Was Habermas’s Communicative Turn a Move in the Wrong Direction?” Maeve Cooke examines the evolution of Jürgen Habermas’s thought over the past five decades. According to Cooke, Habermas’s so-called “communicative turn” was a necessary step in his philosophy’s systematic attempt to derive a universal norm from the immanent context of human practices and institutions. In her opinion, however, Habermas is unable to uphold his pragmatically-based claim to “transcendence from within” without encountering problems of epistemic justification when it comes to his theory’s treatment of normative validity claims. Cooke believes that despite Habermas’ exhaustive efforts, any political theory that discredits the possibility of metaphysical truth inevitably relinquishes the “context-transcending moment” that his idea of validity is meant to capture. In this essay, I examine how Habermasian philosophy attempts to assimilate such criticisms by deriving its normative ideals from the Theory of Communicative Action. In conclusion, I seek to characterize the dilemma thusly: the epistemic criticism raised by Cooke places her in the unenviable position of defending metaphysically-justified validity claims—a pitfall that Habermas’ theory is designed to avoid

Sellars and Quine on Abstracta in Scientific Ontology

Wilfrid Sellars and Willard Van Quine long disagreed over the nature of ontological commitment in scientific inquiry. Particularly, they disagreed over whether abstract entities such as numbers, sets, or classes should be admitted into scientific ontology. In Quine’s view, positing such platonic entities is necessary in order for scientific inquiry to progress and for scientific knowledge to increase. Sellars, on the other hand, sees such a view as a form of platonic realism and eschews it in favor of a more austere nominalism about the ontological status of abstracta. I summarize the reasons for each philosopher’s view, drawing on a dialogue between them regarding the ontological status of abstracta. I argue that Quine’s justifications for his pragmatically-based realism do little to evade Sellars’ charge that such a view commits one to an empirically unjustifiable platonistic ontology. In Sellars’ view, an adequate philosophy of science requires an adequate philosophy of mind, and this implies that we cannot locate unobservable platonic abstracta on an ontological continuum with the unobservable theoretical entities posited in scientific theories (e.g., neutrinos or positrons). Those who are committed to the ideals of scientific realism and methodological naturalism must grapple with the question Sellars posed to Quine: “if sets are basic objects, how does the mind get in touch with them?

The development of the Santa Fe, 1935-1948

Thesis (B.S.)--Massachusetts Institute of Technology, Dept. of Business & Engineering Administration, 1949.Includes bibliographical references (leaves 411-416).by John Walker Barriger, IV.B.S

Influence of respiratory motion management technique on radiation pneumonitis risk with robotic stereotactic body radiation therapy.

Purpose/objectivesFor lung stereotactic body radiation therapy (SBRT), real-time tumor tracking (RTT) allows for less radiation to normal lung compared to the internal target volume (ITV) method of respiratory motion management. To quantify the advantage of RTT, we examined the difference in radiation pneumonitis risk between these two techniques using a normal tissue complication probability (NTCP) model.Materials/method20 lung SBRT treatment plans using RTT were replanned with the ITV method using respiratory motion information from a 4D-CT image acquired at the original simulation. Risk of symptomatic radiation pneumonitis was calculated for both plans using a previously derived NTCP model. Features available before treatment planning that identified significant increase in NTCP with ITV versus RTT plans were identified.ResultsPrescription dose to the planning target volume (PTV) ranged from 22 to 60 Gy in 1-5 fractions. The median tumor diameter was 3.5 cm (range 2.1-5.5 cm) with a median volume of 14.5 mL (range 3.6-59.9 mL). The median increase in PTV volume from RTT to ITV plans was 17.1 mL (range 3.5-72.4 mL), and the median increase in PTV/lung volume ratio was 0.46% (range 0.13-1.98%). Mean lung dose and percentage dose-volumes were significantly higher in ITV plans at all levels tested. The median NTCP was 5.1% for RTT plans and 8.9% for ITV plans, with a median difference of 1.9% (range 0.4-25.5%, pairwise P < 0.001). Increases in NTCP between plans were best predicted by increases in PTV volume and PTV/lung volume ratio.ConclusionsThe use of RTT decreased the risk of radiation pneumonitis in all plans. However, for most patients the risk reduction was minimal. Differences in plan PTV volume and PTV/lung volume ratio may identify patients who would benefit from RTT technique before completing treatment planning

Rib fracture after stereotactic radiotherapy on follow-up thin-section computed tomography in 177 primary lung cancer patients

<p>Abstract</p> <p>Background</p> <p>Chest wall injury after stereotactic radiotherapy (SRT) for primary lung cancer has recently been reported. However, its detailed imaging findings are not clarified. So this study aimed to fully characterize the findings on computed tomography (CT), appearance time and frequency of chest wall injury after stereotactic radiotherapy (SRT) for primary lung cancer</p> <p>Materials and methods</p> <p>A total of 177 patients who had undergone SRT were prospectively evaluated for periodical follow-up thin-section CT with special attention to chest wall injury. The time at which CT findings of chest wall injury appeared was assessed. Related clinical symptoms were also evaluated.</p> <p>Results</p> <p>Rib fracture was identified on follow-up CT in 41 patients (23.2%). Rib fractures appeared at a mean of 21.2 months after the completion of SRT (range, 4 -58 months). Chest wall edema, thinning of the cortex and osteosclerosis were findings frequently associated with, and tending to precede rib fractures. No patients with rib fracture showed tumors > 16 mm from the adjacent chest wall. Chest wall pain was seen in 18 of 177 patients (10.2%), of whom 14 patients developed rib fracture. No patients complained of Grade 3 or more symptoms.</p> <p>Conclusion</p> <p>Rib fracture is frequently seen after SRT for lung cancer on CT, and is often associated with chest wall edema, thinning of the cortex and osteosclerosis. However, related chest wall pain is less frequent and is generally mild if present.</p

Predicting Radiation Pneumonitis after Chemoradiotherapy for Lung Cancer: An International Individual Patient Data Meta-analysis

Radiation pneumonitis is a dose-limiting toxicity for patients undergoing concurrent chemoradiation therapy (CCRT) for non-small cell lung cancer (NSCLC). We performed an individual patient data meta-analysis to determine factors predictive of clinically significant pneumonitis