Galileo and prior philosophy

Galileo claimed inconsistency in the Aristotelian dogma concerning falling bodies and stated that all bodies must fall at the same rate. However, there is an empirical situation where the speeds of falling bodies are proportional to their weights; and even in vacuo all bodies do not fall at the same rate under terrestrial conditions. The reason for the deficiency of Galileo’s reasoning is analyzed, and various physical scenarios are described in which Aristotle’s claim is closer to the truth than is Galileo’s. The purpose is not to reinstate Aristotelian physics at the expense of Galileo and Newton, but rather to provide evidence in support of the verdict that empirical knowledge does not come from prior philosophy.     

‘Spuntar lo scoglio più duro’: did Galileo ever think the most beautiful thought experiment in the history of science?

Still today it remains unclear whether Galileo ever climbed the leaning tower of Pisa in order to drop bodies from its top. Some believe that he established the principle of equal speeds for falling bodies by means of an ingenious thought experiment. However, the reconstruction of that thought experiment circulating in the philosophical literature is no more than a cartoon. In this paper I will tell the story of the thought processes behind the cartoon.     

Galileo and the problem of infinity

During the period before the Greek revolution of 1821, and especially during the years between 1750 and 1821, there were two ways in which European scientific thought was propagated in Greece. The first is traditional. It comes from ancient Greece and, through Byzantium, reaches the period before the Greek revolution. It makes known the thought of Aristotle, Democrititus, and others on ‘natural philosophy’. The second way comes from Europe. The Greek scholars of the period before the Greek revolution, and especially at the end of the eighteenth century, tried to bring to and propagate in Greece the spirit ofthe European Enlightenment, They tried to make known to the Greek people the scientific achievements of Newton, Descartes, Lavoisier, and Laplace. Scientific knowledge is an important weapon against superstition, and Greek students had to learn about science to become free persons in an independent Greek state.     

The role of probability arguments in the history of science

The paper examines Wesley Salmon’s claim that the primary role of plausibility arguments in the history of science is to impose constraints on the prior probability of hypotheses (in the language of Bayesian confirmation theory). A detailed look at Copernicanism and Darwinism and, more briefly, Rutherford’s discovery of the atomic nucleus reveals a further and arguably more important role of plausibility arguments. It resides in the consideration of likelihoods, which state how likely a given hypothesis makes a given piece of evidence. In each case the likelihoods raise the probability of one of the competing hypotheses and diminish the credibility of its rival, and this may happen either on the basis of ‘old’ or ‘new’ evidence.     

Galileo and the problem of concentric circles

In 1892, Eliakim Hastings Moore accepted the task of building a mathematics department at the University of Chicago. Working in close conjuction with the other original department members, Oskar Bolza and Heinrich Maschke, Moore established a stimulating mathematical environment not only at the University of Chicago, but also in the Midwest region and in the United States in general. In 1893, he helped organize an international congress of mathematicians. He followed this in 1896 with the organization of the Midwest Section of the New York City-based American Mathematical Society. He became the first editor-in-chief of the Society's Transactions in 1899, and rose to the presidency of the Society in 1901.     

An overlooked autograph letter of Galileo on the thermometer

Scientism applies the ideas and methods of the natural sciences to the humanities and social sciences. Herbert Spencer applied the law of the conservation of energy to social questions and arrived at formula answers to the issues of the day. The kind of certitude that Spencer aimed for was possible only by ignoring a system of values. Much as he may have believed that he was above personal beliefs, there are values implicit in Spencer's theories and they are the values of the nineteenth-century British middle class. Reasoning by analogy is as valid in social theory as it is in the natural sciences. Spencer's error was in universally applying the idea of the conservation of energy to social systems by means of identity rather than by analogy. Scientists in Britain, where there was a self-assured scientific community, dismissed Spencer's theories as being unscientific, but he enjoyed a vogue in the United States.     

‘One common matter’ in Descartes' physics: the Cartesian concepts of matter quantities,weight and gravity

ABSTRACT

It is common to assume that Descartes did not have a conception of an object's matter density independently of its size, but this is a rather incomplete assessment of the early modern natural philosopher's theory. Key to our understanding of Descartes's physics is a consideration of the ratios between the quantities of the different types of matter in which an object consists. As these ratios determine the degree of an object's porosity and elasticity, they also affect in Descartes's theory the phenomena of gravity and weight.