Foundations of Modern Science: Revolution and Rationalism

The Scientific Revolution: 15th-17th Centuries

Origins and Early Influences

The Scientific Revolution, spanning the 15th to 17th centuries, found its origins in the Middle Ages. It emerged from a critique of the Aristotelian scholastic interpretation, emphasizing the importance of Platonic mathematics.

Key figures laid the groundwork:

• Nicholas of Cusa: Proposed an infinite universe, lacking an absolute center, and supported Neoplatonic ideas.
• Giordano Bruno: Advocated for heliocentrism, further developing Neoplatonic concepts.

Copernicus and the New Cosmic Vision

Nicolaus Copernicus introduced elements that combined an old vision with a new image of the universe. The traditional view considered the universe spherical and adhered to geocentrism. Copernicus, however, proposed a new heliocentric viewpoint.

Ancient thinkers believed orbits were perfect circles. The new vision, championed by figures like Galileo, suggested a homogeneous world.

Galileo's Innovations and the New Science

Galileo Galilei invented the telescope, which allowed observations of the Moon's imperfections and sunspots. This challenged the old vision, which attributed celestial movement to extrinsic and intangible causes, as established by Ptolemy and Aristotle's concept of an unmoved mover.

In contrast, the new science, largely designed by Galileo, explained the universe as infinite. The ancient model, influenced by Pythagorean and Platonic magic (4th-6th century BC), was organic, a model also utilized by Aristotle.

A new mechanistic model emerged, conceptualizing the universe as a clockwork of gears. Atomism, recovered from Democritus (5th century BC), was also embraced, considering the universe as an extension in motion.

Galileo asserted that the new science would be ordered by mathematics. His scientific methodology involved:

1. Observation
2. Hypothesis formulation
3. Deduction of consequences from the hypothesis
4. Experimentation
5. Generalizations or laws (also hypothetical and mathematical)

This methodology was deductive, combining rational and empirical approaches.

Rationalism: The Rise of Cartesian Thought

Descartes and the Foundations of Rationalism

Rationalism arose in France in the 17th century, adopting the deductive method as its cornerstone. Its foremost representative was René Descartes.

The core features of Cartesian Rationalism include:

• Absolute Confidence in Human Reason: Reason alone can lead humanity to the knowledge of truth.
• Innate Ideas: Descartes believed in innate ideas from which other concepts could be deduced to construct a system of the world.
• Search for a New Method: The mathematical method served as the model for this new approach. It was considered obvious and necessary, built upon a priori definitions and axioms (innate truths) from which a complete and closed philosophical system could be derived.
• Subjective and Mechanistic Vision of Reality: Descartes adopted a subjective view of reality, interpreting it through a mechanistic lens.

Descartes, a great scientist, studied the universe and published works supporting Galileo's theses. He did not doubt faith, but rather the truth derived from the senses.

The Problem of Knowledge and Solipsism

Descartes' exploration of the human soul as a thinking substance led to the problem of solipsism, where an individual knows only themselves and is enclosed within their own knowledge. This "problem of knowledge" became central to modern rational philosophy.

The thesis of identity between reason and reality allowed Descartes to construct a Cartesian metaphysics based on the concept of substance.