This document summarizes the development of scientific thought and method. It describes the differences between rationalism, which relies on reason as the source of knowledge, and empiricism, which relies on experience and sensory observation. It discusses key figures like Aristotle, Galileo, and Francesco Redi, and how they helped establish scientific methods like experimentation and control conditions. The scientific method is presented as a systematic process of making observations, developing hypotheses and predictions, conducting experiments to test hypotheses, and analyzing results to either support hypotheses or generate new facts and hypotheses.

1. The Scientific Thought
LCD 105 – Class 12 – Professor Nathacia

2. Rationalism Empiricism
• Reason as source of
knowledge
• Intellectual
• Methods of reasoning:
§ Intuition
§ Deduction
§ Induction
§ Abduction
• Experience as source of
knowledge
• Sensory
• Empirical methods:
§ Observation
§ Experimentation

3. It is needed that we observe the
nature surrounding us in order
to measure it. That way we will
be able to understand the things
we face in the World.
Aristotle

4. • Experiments: METHOD being developed.
• Europe: Development of education (teaching broads minds, questioning being supported).
• Galileo Galilei (1564 — 1642) is the founder of Modern Science. He is the theorist of scientific
method and of autonomy of scientific research.
• Since Galileo, science doesn’t seek the essence of things, but their function.
• The Scientific Revolution established science as responsible for knowledge growth.
• Technology advance plays a core role on Science advance.
Middle Ages
The beginning of Modern Science

5. Aristotle

6. A heavier object falls in a
............ speed than a lighter
object.
Aristotle

7. A heavier object falls in a
FASTER speed than a
lighter object.
Aristotle

8. 1 kg
10 kg
Galileo Galilei

9. A heavier object in free fall will always have
the same acceleration as a lighter object,
despite gravity force being greater in heavier
objects. If we control the shape of the
objects, they will arrive at the ground at the
same time, even if one weights 1 kilogram
and the other weights 10 kilogram.
Galileo Galilei

10. W=mx g
g=9,8 m/s
Same acceleration = same speed
same speed + same height = same
falling duration
Scientific method visualizing
conditions (including the non-
apparent ones) and discerning their
effects.
Galileo Galilei

11. Aristotle

12. There is spontaneous generation,
Abiogenesis, from an active
principle/agent.
Aristotle

13. Francesco Redi

14. Any type of life can only come
from another live thing.
Method with control condition.
Francesco Redi

15. “Do not believe in anything simply because you
have heard it. Do not believe in anything simply
because it is spoken and rumored by many. Do not
believe in anything simply because it is found
written in your religious books. Do not believe in
anything merely on the authority of your teachers
and elders. Do not believe in traditions because
they have been handed down for many
generations. But after observation and analysis,
when you find that anything agrees with reason
and is conducive to the good and benefit of one
and all, then accept it and live up to it”
- Buddha

17. • Scientific Method is the sistemathic attempt of turning those limitations
around.
• It is the set of procedures to help us on the task of not getting fooled by
ourselves.
• Science seeks objective measures that can be confirmed in independente
events.
• It demands evidences open to
public judgement.
• Personal testimonies are under
valued.

18. DEDUCTION
Deductive reasoning is when one gets to a particular
truth from a more general one. Therefore, when we
include a more specific fact into a more general one, we
are reasoning through deduction.
1) A always equals B (general fact, also known by first
premise);
2) There is an X that equals A (particular case or
second premise);
3) Therefore, this X equals B (conclusion).

19. Inductive reasoning is when we go the opposite way:
observing particular cases, isolated, we look for a pattern,
or a general rule that can explain and be applied to all
observed cases.
1)All observed As equal B (data observation, isolated
facts);
2)Therefore, all A equals B.
INDUCTION

20. Deductive reasoning: immediate inferences, syllogism or
conditional argumentation.
All animals are mortal
All men are animals
Therefore, all men are mortal
Inductive reasoning: from particular cases to general
inferences; predictions.
Copper conducts electricity.
Iron conducts electricity.
Silver conducts electricity.
Gold conducts electricity.
Copper, iron, silver and gold are metals.
Metals are electrical conductors.
DEDUCTION VS. INDUCTION

21. Vídeo: https://www.youtube.com/watch?v=-X8Xfl0JdTQ

22. POPPER:
A theory is only scientific when it is refutable by a
conceivable event.
The aim is not to prove a hypothesis right, but to prove it
wrong.
The point is the more you fail in prove your hypothesis
wrong, the more it is reliable (probability).
It is true just for that moment under that conditions.
FALSIFYABILITY

23. x=y: A world of equalities doesn’t leave space for
questioning;
x≠y: A world of inequalities (extreme relativism)
also doesn’t leave space for questioning, or
reasoning.
What leads us to a conditional world:
If x equals ........, then y equals ......
THE WORKING SPACE OF THE
SCIENTIFIC METHOD

24. SCIENTIFIC THEORY
Set of all facts and
hypothesis concerned the
object of study
Observation
Ø Systematic
Ø Controlled
Facts
Ø Verifiable
Hypothesis
Ø Testable
Ø Falsifiable
Predictions
Ø Implications
Ø (partial) conclusions
Experiments
Ø New observations
Ø Logical Analysis
New facts
Recycle
hypothesis
Do results
support the
hypothesis?
The Scientific Method
YES
NO