Month: February 2007

8 – Plato, Part III: Arguments for the Immortality of the Soul (cont.)

8 – Plato, Part III: Arguments for the Immortality of the Soul (cont.)

The lecture focuses exclusively on one argument for the immortality of the soul from Plato’s Phaedo, namely, “the argument from simplicity.” Plato suggests that in order for something to be destroyed, it must have parts, that is, it must be possible to “take it apart.” Arguing that the soul is simple, that it does not have parts, Plato believes that it would logically follow that the soul is indestructible.

7 – Direct Imaging of Exoplanets

7 – Direct Imaging of Exoplanets

Class begins with a problem on transits and learning what information astronomers obtain through observing them. For example, radii of stars can be estimated. Furthermore, applying the Doppler shift method, one can find the mass of a star. Finally, a star’s density can be calculated. A second method for identifying planets around stars is introduced: the astrometry method. The method allows for an extremely accurate assessment of a star’s precise position in the sky. Special features of the astrometry method are discussed and a number of problems are solved. A short summary is given on the three methods astronomers use to identify exoplanets. Class ends with an overview of upcoming space missions and the hope of detecting the presence of biological activity on other planet.

7 – Plato, Part II: Arguments for the Immortality of the Soul

7 – Plato, Part II: Arguments for the Immortality of the Soul

The discussion of Plato’s Phaedo continues, presenting more arguments for the existence and immortality of the soul. One such argument is “the argument from the nature of the forms,” which states that because the forms are non-physical objects and cannot be grasped by something physical like the body, it follows that they must be grasped by the soul which must be non-physical as well. This argument is followed by the “argument from recycling” and “the argument from recollection.”

6 – Microlensing, Astrometry and Other Methods

6 – Microlensing, Astrometry and Other Methods

The class begins with a discussion on transits – important astronomical events that help astronomers to find new planets. The event occurs when a celestial body moves across the face of the star it revolves around and blocks some of its light. By calculating the amount of light that is being obscured astronomers can obtain important information about both star and planet, such as size, density, radial velocity and more. The concept of planetary migration is explained in order to better understand the dramatic differences between bodies in the Inner and Outer Solar System. Finally, potential problems in the Solar System that may occur as a result of migration are addressed.

6 – Arguments for the Existence of the Soul, Part IV; Plato, Part I

6 – Arguments for the Existence of the Soul, Part IV; Plato, Part I

The lecture begins with a continued discussion of the Cartesian argument and its weaknesses. The lecture then turns to Plato’s metaphysical views in the context of his work, Phaedo. The key point in the discussion is the idea that in addition to the ordinary empirical world that we are familiar with, we posit the existence of a second realm in which the Platonic forms exist. These forms are the abstract properties that we attribute to physical objects, such as beauty, justice, goodness and so on. Since it is the soul that conceives of these Platonic forms and ideas, Plato argues that the soul not only outlives the body but lasts forever. It is perfect, immaterial and indestructible.