What Is it Like to Be a Bat? perceptional experiences. While it is possible to imagine what it would be like to fly, navigate by sonar, hang upside down and eat insects like a bat, that is not the same as a bat's perspective. Nagel claims that even if humans were able to metamorphose gradually into bats, their brains would not have been wired as a bat's from birth; therefore, they would only be able to experience the life and behaviors of a bat, rather than the mindset. Such is the difference between subjective and objective points of view. According to Nagel, "our own mental activity is the
Enantiomeric excess of the optical purity is identical to the enantiomeric excess. This has led to informal use the two terms as interchangeable, especially because optical purity was the traditional way of measuring enantiomeric excess. However, other methods such as chiral column chromatography and NMR spectroscopy can now be used for measuring the amount of each enantiomer individually. The ideal equivalence between enantiomeric excess and optical purity does not always hold. For example, The term enantiomeric excess was introduced in 1971 by Morrison and Mosher in their publication "Asymmetric Organic Reactions". The use of enantiomeric excess has established itself because of its