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Foundations of the Scientific Method

The scientific method is a systematic approach to investigating phenomena and acquiring new knowledge. It is based on empirical observation, logical reasoning and critical examination.

What Is Science?​

Science can be defined as:

  • A systematic process for acquiring knowledge about the world through observation, experiment and analysis
  • A collection of methods for investigating phenomena
  • A body of knowledge acquired through these methods
  • A community of researchers who work according to shared standards

Characteristics of science:

  • Empirical: Based on observation and experience, not on intuition or authority
  • Systematic: Follows structured methods and procedures
  • Objective: Strives to minimise subjective influences
  • Provisional: Results are regarded as provisional and revisable
  • Public: Methods and results are made transparent
  • Self-correcting: Errors are discovered and corrected through continuous examination

The Scientific Process​

The scientific process is often presented as a cyclical sequence comprising the following steps:

  1. Observation and question: The process begins with the observation of a phenomenon and the formulation of a question.

Example: A doctor observes that patients who take aspirin regularly suffer heart attacks less frequently, and wonders whether there is a causal connection.

  1. Literature review: Existing research and theories are examined in order to understand the current state of knowledge.

Example: The doctor researches scientific studies on aspirin and cardiovascular disease.

  1. Formulating a hypothesis: A testable explanation or prediction is formulated.

Example: "Regular intake of low-dose aspirin reduces the risk of heart attacks in patients with certain risk factors."

  1. Experimental design: An experiment or study is designed to test the hypothesis.

Example: A randomised controlled trial in which one group of at-risk patients receives aspirin and a control group receives a placebo.

  1. Data collection: The experiment is carried out and data are collected.

Example: Over several years, data on heart attacks are collected in both groups.

  1. Data analysis: The collected data are analysed in order to identify patterns, trends or correlations.

Example: Statistical analysis of the heart attack rate in both groups.

  1. Interpretation: The results are interpreted in the context of the original hypothesis.

Example: The data show that the aspirin group has a 25% lower heart attack rate.

  1. Conclusion: Based on the interpretation, conclusions are drawn and the hypothesis is accepted, modified or rejected.

Example: The hypothesis is accepted, but with the qualification that the benefit applies only to certain risk groups.

  1. Communication: The results are published in scientific journals and submitted to the scientific community for review.

Example: Publication of the study results in a medical journal.

  1. Replication and extension: Other scientists attempt to replicate or extend the results.

Example: Further studies investigate the effect of aspirin in different patient groups or with different dosages.

This process is not always linear and may go through several iterations. Scientists often return to earlier steps when new findings require it.

Hypotheses and Theories​

In science, terms such as "hypothesis" and "theory" have specific meanings that differ from their everyday usage.

Hypotheses​

A hypothesis is a provisional, testable explanation for an observed phenomenon. It serves as a starting point for further investigation.

Characteristics of a good scientific hypothesis:

  • Testable: It must be verifiable through observation or experiment.
  • Falsifiable: It must be possible to specify conditions under which the hypothesis would be shown to be false.
  • Precise: It should be formulated clearly and unambiguously.
  • Relevant: It should relate to the phenomenon under investigation.
  • Simple: It should follow the principle of parsimony (Occam's razor) and not be unnecessarily complex.

Examples of hypotheses:

  • "Plants exposed to classical music grow faster than plants not exposed to any music."
  • "Taking vitamin C reduces the duration of colds."
  • "Raising the minimum wage leads to an increase in unemployment."

Theories​

A theory in science is not simply a guess or speculation, as the term is often used colloquially. A scientific theory is a comprehensive, well-confirmed explanatory model supported by numerous observations and experiments.

Characteristics of a scientific theory:

  • Explanatory power: It offers a coherent explanation for a wide range of phenomena.
  • Predictive power: It makes it possible to make predictions about future observations or experiments.
  • Empirical support: It is supported by extensive empirical evidence.
  • Consistency: It is in agreement with other established theories and knowledge.
  • Fruitfulness: It generates new research questions and directions.

Examples of scientific theories:

  • The theory of evolution
  • The theory of relativity
  • Quantum theory
  • The germ theory of disease
  • Plate tectonics

The Path from Hypothesis to Theory​

A hypothesis can develop into a theory through repeated confirmation and extension. This process involves:

  • Repeated testing of the hypothesis under various conditions
  • Accumulation of supporting evidence
  • Refutation of alternative explanations
  • Integration into a broader theoretical framework
  • Acceptance by the scientific community

It is important to understand that even established theories in science are never regarded as absolutely "proven". They remain in principle open to revision or replacement when new evidence requires it. This openness to revision is a strength, not a weakness, of science.

Induction and Deduction in Science​

Scientific thinking combines two fundamental modes of reasoning: induction and deduction.

Induction​

Induction is the process of moving from specific observations to general principles. It is a "bottom-up" approach.

Example of inductive reasoning:

  1. Observation: All swans observed so far have been white.
  2. Conclusion: All swans are white.

Induction is important for forming hypotheses and developing theories, but it has inherent limits. The "problem of induction" (formulated by David Hume) points out that we can never infer universal laws from limited observations with absolute certainty. The discovery of black swans in Australia, for example, refuted the inductive conclusion that all swans are white.

Deduction​

Deduction is the process of moving from general principles to specific predictions. It is a "top-down" approach.

Example of deductive reasoning:

  1. General principle: All humans are mortal.
  2. Specific case: Socrates is a human.
  3. Conclusion: Socrates is mortal.

Deduction is important for deriving testable predictions from theories. If the prediction does not come true, the theory must be revised.

Abduction​

In addition to induction and deduction, abduction (sometimes referred to as "inference to the best explanation") also plays an important role in science. Abduction is the process of finding the best explanation for a set of observations.

Example of abductive reasoning:

  1. Observation: The lawn is wet.
  2. Possible explanations: It has rained; the sprinkler system was on; someone watered the lawn with a hose.
  3. Additional observation: The street is also wet.
  4. Conclusion: The best explanation is that it has rained.

Abduction is particularly important in the early phase of scientific investigation, when hypotheses are being developed.

Empirical Methods​

Empirical methods are procedures for the systematic collection and analysis of data from observation or experience. They form the backbone of scientific research.

Observation​

Observation is the systematic recording of phenomena in their natural environment.

Types of observation:

  • Structured vs. unstructured observation: In structured observation, predefined categories are used, whereas unstructured observation is more open.
  • Participant vs. non-participant observation: In participant observation, the observer is part of the context under investigation, whereas in non-participant observation they remain outside it.
  • Overt vs. covert observation: In overt observation, those observed know that they are being observed, whereas in covert observation they are unaware of it.

Example: Jane Goodall's groundbreaking research on chimpanzees was based on years of participant observation in the wild.

Experiment​

Experiments are controlled investigations in which variables are manipulated in order to identify cause-and-effect relationships.

Key features of experiments:

  • Manipulation: The researcher manipulates the independent variable.
  • Control: Other variables are kept constant or controlled.
  • Randomisation: Participants are randomly assigned to conditions in order to minimise bias.
  • Replication: The experiment can be repeated in order to confirm the results.

Example: In a classic experiment on the efficacy of a new drug, one group receives the drug (experimental group), while another group receives a placebo (control group). The participants are randomly assigned to the groups, and neither they nor the researchers know who receives which treatment (double-blind procedure).

Surveys and Interviews​

Surveys and interviews are methods for collecting data about people's attitudes, beliefs, experiences or behaviour.

Types of surveys and interviews:

  • Structured interviews/surveys: Use standardised questions in a fixed order.
  • Semi-structured interviews: Combine prepared questions with the flexibility to follow up.
  • Open interviews: Allow a free conversation about certain topics.
  • Focus groups: Group interviews that make use of interactions between participants.

Example: The regular opinion polls before elections that capture voters' intentions.

Case Studies​

Case studies are intensive investigations of individual cases (people, groups, organisations, events) that provide deep insights into complex phenomena.

Characteristics of case studies:

  • Depth rather than breadth: A detailed investigation of a few cases instead of a superficial analysis of many cases.
  • Multiple data sources: A combination of various methods and sources.
  • Context-related: Consideration of the specific context of the case.
  • Process-oriented: A focus on developments and changes over time.

Example: Oliver Sacks's neurological case studies, as described in The Man Who Mistook His Wife for a Hat, which offer deep insights into neurological disorders.

Scientific Disciplines and Their Methods​

Different scientific disciplines have developed different methodological approaches appropriate to their specific objects of research.

Natural Sciences​

The natural sciences (physics, chemistry, biology, etc.) study the natural world and its phenomena.

Methodological characteristics:

  • A strong focus on controlled experiments
  • Quantitative measurements and mathematical modelling
  • A search for general laws
  • A high degree of precision and control

Example: In physics, hypotheses are often tested through precise measurements under strictly controlled conditions, as in the detection of the Higgs boson at CERN.

Social Sciences​

The social sciences (psychology, sociology, economics, etc.) study human behaviour and social phenomena.

Methodological characteristics:

  • A combination of quantitative and qualitative methods
  • Consideration of cultural and contextual factors
  • Ethical constraints on experiments involving humans
  • Challenges in controlling variables

Example: In psychology, laboratory experiments are often combined with field studies and surveys in order to obtain a more comprehensive picture of human behaviour.

Humanities​

The humanities (history, philosophy, literary studies, etc.) study human culture, ideas and forms of expression.

Methodological characteristics:

  • Hermeneutic and interpretive approaches
  • Textual analysis and source criticism
  • Historical and contextual embedding
  • Reflection on values and meanings

Example: In the study of history, historical documents are critically analysed and interpreted in order to understand past events and their significance.

Interdisciplinary Approaches​

Increasingly important are interdisciplinary approaches, which combine the methods and perspectives of various disciplines in order to investigate complex problems.

Examples:

  • Cognitive science connects psychology, neuroscience, linguistics, philosophy and computer science.
  • Environmental science integrates biology, chemistry, geology, economics and political science.
  • Science and technology studies combine sociological, historical and philosophical approaches.