BackgroundIn the Canadian Alliance for Healthy Hearts and Minds (CAHHM) cohort, participants underwent magnetic resonance imaging (MRI) of the brain, heart, and abdomen, that generated incidental findings (IFs). The approach to managing these unexpected results remain a complex issue. Our objectives were to describe the CAHHM policy for the management of IFs, to understand the impact of disclosing IFs to healthy research participants, and to reflect on the ethical obligations of researchers in future MRI studies.MethodsBetween 2013 and 2019, 8252 participants (...) (mean age 58 ± 9 years, 54% women) were recruited with a follow-up questionnaire administered to 909 participants (40% response rate) at 1-year. The CAHHM policy followed a restricted approach, whereby routine feedback on IFs was not provided. Only IFs of severe structural abnormalities were reported.ResultsSevere structural abnormalities occurred in 8.3% (95% confidence interval 7.7–8.9%) of participants, with the highest proportions found in the brain (4.2%) and abdomen (3.1%). The majority of participants (97%) informed of an IF reported no change in quality of life, with 3% of participants reporting that the knowledge of an IF negatively impacted their quality of life. Furthermore, 50% reported increased stress in learning about an IF, and in 95%, the discovery of an IF did not adversely impact his/her life insurance policy. Most participants (90%) would enrol in the study again and perceived the MRI scan to be beneficial, regardless of whether they were informed of IFs. While the implications of a restricted approach to IF management was perceived to be mostly positive, a degree of diagnostic misconception was present amongst participants, indicating the importance of a more thorough consent process to support participant autonomy.ConclusionThe management of IFs from research MRI scans remain a challenging issue, as participants may experience stress and a reduced quality of life when IFs are disclosed. The restricted approach to IF management in CAHHM demonstrated a fair fulfillment of the overarching ethical principles of respect for autonomy, concern for wellbeing, and justice. The approach outlined in the CAHHM policy may serve as a framework for future research studies.Clinical trial registrationhttps://clinicaltrials.gov/ct2/show/nct02220582. (shrink)

In elementary logic textbooks, Venn diagrams are used to analyze and evaluate the validity of syllogistic arguments. Although the method of Venn diagrams is shown to be a powerful analytical tool in these textbooks, it still has limitations. On the one hand, such method fails to represent singular statements of the form, “a is F.” On other hand, it also fails to represent identity statements of the form, “a is b.” Because of this, it also fails to give an account (...) of the validity of some obviously valid arguments that contain these types of statements as constituents. In this paper, owing to the developments in the literature on Venn diagrams, we offer a way of supplementing the rules of the Venn diagram found in textbooks, and show how this retooled Venn diagram technique could account for the problem cases. (shrink)

Context: The dominant approach to the study of perception is representational/computational, with an emphasis on the achievements of the brain and the nervous system, which are taken to construct internal models of the world. Alternatives include ecological, embedded, embodied, and enactivist approaches, all of which emphasize the centrality of action in understanding perception. Problem: Despite sharing many theoretical commitments that lead to a rejection of the classical approach, the alternatives are characterized by important contrasts and points of divergence. Here we (...) focus on the enactive and ecological approaches, in particular, on how they construe the status of the environment and the content of perception. Method: We begin with a review of James Gibson’s ecological psychology, highlighting it as a psychology for all organisms not just humans. Against this backdrop, we consider enactivist arguments against direct perception - a central assertion of the ecological approach - and in favor of interpreting the activity of perceptual agents as a kind of construction of a perceptually meaningful world. Results: We assess the merits of this interpretation and we conclude that it cannot be grounded on fundamental principles such as thermodynamics and organism-environment mutuality. Implications: As a consequence, enactivism remains close to representationalism and entails a form of dualism. Constructivist content: We advance a criticism of the constructivist foundations of the enactive approach to perception. Perception-action mutuality at the heart of enactivism does not require mental construction; indeed, perception-action mutuality obviates construction. (shrink)

I examine two strands in Locke's thought which seem to conflict with his corpuscularian sympathies: his repeated suggestion that natural philosophy is incapable of being made a science, and his claim that some of the properties of bodies--secondary qualities, powers of gravitation, cohesion and maybe even thought--are arbitrarily "superadded" by God. ;Locke often says that a body's properties flow from its real essence as the properties of a triangle flow from its definition. He is widely read as having thought that (...) if we had ideas of a body's real essence, we would be able to perceive a priori a necessary connection between that body's real essence and its observable properties. I argue that this leaves Locke's skepticism without any rationale, making it depend entirely upon our ignorance of corpuscular structures when in fact he never rules out the possibility of our acquiring ideas of corpuscular structures through improvements in microscopy. I argue that Locke's geometrical analogy is better understood as an endorsement of deductivism about scientific explanation. He thinks that knowledge of corpuscular structures is a necessary, but not a sufficient, condition for scientific knowledge of bodies. The deeper source of his skepticism is his view that we cannot have universal and certain knowledge of the laws of nature because they are contingent. ;I approach the subject of Locke's attitude toward mechanism by examining his superaddition doctrine. In contrast with M. R. Ayers, I attribute to Locke what I call strong voluntarism: the view that a body's powers to interact with other bodies are not fully determined by the essence of matter, and that they are at least partly determined by the will of God. I argue that Descartes and Boyle are also strong voluntarists, but that Locke's voluntarism differs in that he maintains that bodies have some powers which are not even partly explicable in terms of the motions of matter. Locke's position is thus incompatible with the mechanism of Descartes and Boyle. (shrink)

This is a close scrutiny of "De Anima II 5", led by two questions. First, what can be learned from so long and intricate a discussion about the neglected problem of how to read an Aristotelian chapter? Second, what can the chapter, properly read, teach us about some widely debated issues in Aristotle's theory of perception? I argue that it refutes two claims defended by Martha Nussbaum, Hilary Putnam, and Richard Sorabji: (i) that when Aristotle speaks of the perceiver becoming (...) like the object perceived, the assimilation he has in mind is ordinary alteration of the type exemplified when fire heats the surrounding air, (ii) that this alteration stands to perceptual awareness as matter to form. Claim (i) is wrong because the assimilation that perceiving is is not ordinary alteration. Claim (ii) is wrong because the special type of alteration that perceiving is is not its underlying material realisation. Indeed, there is no mention in the text of any underlying material realisation for perceiving. The positive aim of II 5 is to introduce the distinction between first and second potentiality, each with their own type of actuality. In both cases the actuality is an alteration different from ordinary alteration. Perception exemplifies one of these new types of alteration, another is found in the acquisition of knowledge and in an embryo's first acquisition of the power of perception. The introduction of suitably refined meanings of 'alteration' allows Aristotle to explain perception and learning within the framework of his physics, which by definition is the study of things that change. He adapts his standard notion of alteration, familiar from "Physics" III 1-3 and "De Generatione et Corruptione" I, to the task of accounting for the cognitive accuracy of (proper object) perception and second potentiality knowledge: both are achievements of a natural, inborn receptivity to objective truth. Throughout the paper I pay special attention to issues of text and translation, and to Aristotle's cross-referencing, and I emphasise what the chapter does not say as well as what it does. In particular, the last section argues that the textual absence of any underlying material realisation for perceiving supports a view I have defended elsewhere, that Aristotelian perception involves no material processes, only standing material conditions. This absence is as telling as others noted earlier. Our reading must respect the spirit of the text as Aristotle wrote it. (shrink)

It is a standing temptation for philosophers to find anticipations of their own views in the great thinkers of the past, but few have been so bold in the search for precursors, and so utterly mistaken, as Berkeley when he claimed Plato and Aristotle as allies to his immaterialist idealism. InSiris: A Chain of Philosophical Reflexions and Inquiries Concerning the Virtues of Tar-Water, which Berkeley published in his old age in 1744, he reviews the leading philosophies of antiquity and finds (...) them on the whole a good deal more sympathetic to his own ideas than the ‘modern atheism’, as he calls it, of Hobbes and Spinoza or the objectionable principles of ‘the mechanic and geometrical philosophers’ such as Newton. But his strongest and, I think, his most interesting claim is that neither Plato nor Aristotle admitted ‘an absolute actual existence of sensible or corporeal things’. (shrink)

The question contrasts two ways of expressing the role of the sense organ in perception. In one the expression referring to the sense organ is put into the dative case ; the other is a construction with the preposition δiá governing the genitive case of the word for the sense organ.

There is general acknowledgement that both the anterior cingulate and orbitofrontal cortex are implicated in reinforcement-guided decision making, and emotion and social behaviour. Despite the interest that these areas generate in both the cognitive neuroscience laboratory and the psychiatric clinic, ideas about the distinctive contributions made by each have only recently begun to emerge. This reflects an increasing understanding of the component processes that underlie reinforcement- guided decision making, such as the representation of reinforcement expectations, the exploration, updating and representation (...) of action values, and the appreciation that choices are guided not just by the prospect of reward but also by the costs that action entails. Evidence is emerging to suggest that the anterior cingulate and orbitofrontal cortex make distinct contributions to each of these aspects of decision making. (shrink)

Background: Informed consent is regarded as a contract between autonomous and equal parties and requires the elements of information disclosure, understanding, voluntariness and consent. The validity of informed consent for critically ill patients has been questioned. Little is known about how these patients experience the process of consent.Objective: The aim of this study was to explore critically ill patients’ experience with the principle of informed consent in a clinical trial and their ability to give valid informed consent.Design: 11 stroke patients (...) who had been informed about thrombolytic treatment and had been through the process of deciding whether or not to participate in a thrombolysis trial went through repeated qualitative semistructured interviews.Results: None of the patients had any clear understanding of the purpose of the trial. Neither did they understand the principles of randomisation and voluntariness. Reasons for giving or not giving consent were trust, conceptions of benefits and risks and altruism. Several patients found it immoral to involve patients in the consent procedure and argued that this was the doctors’ responsibility. Others argued that it is a duty to question patients and perceived it as a sign of being treated with respect and dignity. A majority of the patients found the consent process vague and ambiguous.Conclusions: The results indicate that the principle of informed consent from critically ill patients cannot be seen as a contract between equal and autonomous parties. Further studies are needed to explore critically ill patients’ experiences with the process of informed consent. (shrink)

Theaetetus, asked what knowledge is, replies that geometry and the other mathematical disciplines are knowledge, and so are crafts like cobbling. Socrates points out that it does not help him to be told how many kinds of knowledge there are when his problem is to know what knowledge itself is, what it means to call geometry or a craft knowledge in the first place—he insists on the generality of his question in the way he often does when his interlocutor, asked (...) for a definition, cites instead cases of the concept to be defined. (shrink)