Definition of Science

• Many today would identify knowledge with science, especially natural sciences
• Science has become the archetype of knowledge
• The prestige, relevance, and importance of science invite a better understanding of its successes and limitations
• In the 21st century Western culture views a world without science as inconceivable
• Scientific knowledge is inseparable from our way of life.
• Science, allied with technology, helps humanity control and modify the environment to improve living conditions
• Science also satisfies the desire to acquire a greater understanding of the world
• Nowadays, science has two clear objectives:
• Greater knowledge of the world (natural and social)
• Establishing practical applications of knowledge to improve our existence
• According to the text, the next two themes will study what science is, offer a classification of sciences and focus on the analysis of the natural sciences

Definition of Science

• The word "science" comes from the Latin "scientia," meaning "certain knowledge of things through their principles and causes."
• Science refers to both a body of knowledge and the methods/tools to acquire that knowledge
• Aristotle defined science as "the knowledge of things through their causes" and said to truly know something, one must know why it happens.
• According to Aristotle, to know something, one must know not only that it happens, but also why it happens
• Aristotle's notion of causality isn't fully shared today
• Aristotle believed in four causes: formal, material, agent, and final.
• Modern science focuses almost exclusively on the efficient (agent) and material causes, dismissing the final cause
• Modern science arose by modifying the Aristotelian notion of causality
• Science seeks to achieve an explanation and description of the world that is true and demonstrable
• Science uses precise language to express knowledge in laws and theories and its characterized by empirical contrastability

Evolution of Science

• The current concept of knowledge has not remained unchanged throughout history
• The concept of the universe has also evolved
• Some science characteristics have varied, yet it shares rational, systematic, critical traits with philosophy
• Science originated in the 6th century BC, like philosophy, and emerged again in the 16th-17th centuries with the scientific revolution
• There was no distinction between science and philosophy in Antiquity and the Middle Ages
• The separation of science and philosophy will be sketched, focusing on the birth of modern science within the natural sciences which began in the nineteenth and twentieth centuries.
• Scientific revolution: occurred during the 16th and 17th centuries, deeply changing knowledge and the concept of the universe in the area of physics, specifically in kinetics and astronomy

Characteristics of the New Knowledge

• Abandonment of studying essences and universals (Aristotelian formal cause).
• Focus on understanding the material world, concrete entities and their characteristics
• Elimination of the final cause from understanding the world; focusing on how things happen, not why
• Introduction of scientific experimentation to test laws and theories, with Galileo Galilei emphasizing this aspect
• Science uses mathematical language, expressing nature's properties objectively and quantifiably
• Descartes and Galileo stressed the importance of mathematical language
• Middle Ages knowledge was excessively speculative, more interested in abstract features than the changing world

Impact on Technical Knowledge

• The development of the arts changed the conception of technical knowledge
• Technical knowledge improves with theoretical knowledge.
• Practical application of knowledge can greatly improve human life, making it better.
• The new science focuses on material phenomena, separating spirit and matter
• New science methods were applicable to studying the natural world, leading to the claim that only genuine knowledge exists in that realm
• In the mid-19th century, rigorous and objective knowledge of "human" issues (history, society, etc.) became accepted using specific techniques

Difference Between Science and Philosophy

• Science and philosophy began to differentiate in methods, objectives, and procedures leading to a separation
• Newton considered his knowledge within Natural Philosophy (the study of the natural world)
• The separation culminated in the 19th century as some considered that knowledge must use the experimental method and mathematical language.

Current Considerations

• Scientists now recognize the importance of philosophy, acknowledging there is no single method for all knowledge aspects.
• Philosophical knowledge cannot ignore the contributions of science, and there's a close relationship between the two.

Classification of Sciences

• Traditional science classification divides it into empirical and formal sciences
• Empirical sciences explore the world (natural or social), explaining and predicting events
• Empirical sciences statements must be tested with factual evidence
• Formal sciences don't need factual confirmation as its propositions are self-proving, like mathematics and logic

Division of Empirical Sciences

• Sciences are divided into social and natural sciences
• Natural sciences investigate the physical world, independent of human actions, like biology, physics, chemistry, and geology
• Social or human sciences analyzes the world created by humans, such as history, politics, linguistics, economics, and sociology

Sciences Applied

• Fields like medicine, architecture, engineering, and biotechnology will be missed due to their lack of theory as they are considered practical knowledge, but relate to Sciences Applied classification
• With the current tight relationship between science and application, the traditional classification is outdated

Language of Natural Sciences

• Science aims to formulate objective and universally valid laws to explain events
• Concepts are the basis of science, striving for objectivity and relating to each other in laws and theories
• Concepts are abstract entities that allow us to identify, differentiate objects
• Science categorizes reality objectively, avoiding ambiguities of natural language

Types of Scientific Concepts

• Classificatory concepts: categorize reality; e.g., cells are classified as eukaryotes and prokaryotes
• The periodic table of elements is another example each element is defined by protons in the atom's nucleus.
• Comparative concepts: classify and order things into sets, like density, antiquity, or hardness
• They establish degree differences when applied to entities
• Metric concepts: identify objects by magnitudes, enabling mathematical operations for accurate predictions.

Scientific Laws

• Scientific laws take universal form, indicating a regular, constant relationship between phenomena or aspects
• It states that under conditions X, condition Y will always occur without exception.
• Boyle-Mariotte's law relates the pressure and volume of gases which says that the pressure exerted by chemical force is inversely proportional to the gaseous mass
  • As volume increases, pressure decreases, and vice versa, when there is constant temperature

Examples of Laws

• Gay-Lussac's law: establishes that the pressure of a fixed volume of gas is directly proportional to the temperature
• Law of Gravity: F=G m₁x m²/r²
• Laws describe observable facts and can be tested through scientific experimentation
• Universality: laws express regularities of nature, all related phenomena are subject to them
• Necessary: describe how things are, and how they cannot be otherwise Capacity for prediction: the capacity to anticipate future events from current parameters
• Deterministic laws are universal and necessary, and there are also probabilistic laws
• Probabilistic laws establish the likelihood of an event rather than a constant relationship
• Radioactive decay is a random phenomenon where atoms of each radioactive element have a characteristic probability of disintegration
• Mean life of radium226 is 1620 years, polonium218 is 3.05 minutes
• Scientific laws shouldn't be confused with political, ethical, or moral laws
• The former expresses nature's regularity, and the second indicates how humans should behave to achieve a society that is as fair as possible

Scientific Theories

• Science aims to explain the reality of an event, not just show regularities in laws, and the scientist makes an attempt to connect those laws to have vision of nature that is the most global as possible
• Scientific theories connect laws to form coherent and compact systems
• A theory is a set of concepts, quantifiable properties, and laws that provide a framework for explaining a field of reality
• Scientific theories allow predicaments about behavior of the world in order to intervene
• Scientific theories also try to explain the regularities expressed by laws and gives better understanding and depth of phenomena
• Characteristics for a good theory is helping to predict and explain phenomena which where unknown when formulating the theory.
• Scientific theories help understanding the universe as expressions of underlying processes and structures that adjust specific principles that are contrastable
• The corpuscular and undulatory theory of light, the kinetic theory of gases, or the theory of evolution are examples