Rationalism: what it is, types and examples to apply in everyday life

Rationalism is a philosophical current that defends that the origin of all true knowledge comes from human reason. Let’s see what specific applications it has.

Last update: April 24, 2022

Rationalism is a philosophical current that argues that reason is the main way of acquiring knowledge. This position arose in continental Europe during the 17th and 18th centuries and is considered to have been founded by René Descartes.

The postulate that true knowledge comes from the ability to reason marked a substantial change in the history of thought. Well, until then the belief prevailed that religious faith and the word of God were the only sources.

Next we will present what rationalism consists of and how it is applied in everyday life.

Origin of rationalism

The origin of rationalism set in the scientific revolution of the 17th century, context that introduced the problem of knowledge (its origin and foundation) in the philosophical debates of the time. From there two great philosophical currents arose: rationalism and empiricism. Both share the confidence in the new science, but they have differences.

While rationalism emphasizes the role of reason in the acquisition of knowledge, empiricism emphasizes the role of experience and evidence as the main sources.

The founder of rationalism was the French philosopher René Descartes, who aspired to turn philosophy into a scientific discipline, provided with a method in which the role of reason would dominate. Thus, in his work The speech of the methodproposes a procedure (popularly known as cartesian method) to reach true knowledge through doubt.

This method consisted of 4 rules:

  1. Evidence: Only that which does not cause doubt is true.
  2. Analysis: reduce the complex to simpler parts to understand it.
  3. Deduction: identify complex truths from simple ones already known.
  4. Verification: check if the discovered from the reason was found through the rules already mentioned.

Subsequently, philosophers such as Nicolas Malebranche, Baruch Spinoza and Gottlieb Leibniz formulated their rationalist positions on the origin of knowledge, which is why they are also recognized as the main exponents of this movement.

René Descartes could be recognized as the founder of modern rationalism.

Characteristics of rationalism

Within rationalism there are different positions on knowledge. For example, the rationalism of Descartes is not the same as that of Leibniz or Spinoza.

However, they all share essential characteristics. These are the following:

  • The conviction that reason is the main source of true knowledge and that it is above other instances such as faith, authority, the irrational or empirical experience.
  • The belief that the human being comes into the world with innate ideas (generally put there by God or the divinity), so the act of knowing implies identifying these ideas through reason.
  • Defends that the senses are capable of deceiving usTherefore, experience alone is not a reliable source for accessing the truth. This postulate makes rationalism oppose empiricism.
  • The deductive method is prioritized in the acquisition of knowledge.
  • The belief that reason is limitless and it is the source of all human progress.


As we have already said, within this philosophical current there are different positions. Among them, the following stand out:

  • Theological: defends that God is the one who guides humanity. Therefore, reason is the best way to access the knowledge provided by the divinity.
  • Logic: considers that thought is the only source of knowledge.
  • Immanent: based on the innate ideas of Descartes.
  • Transcendent: it holds that the world of experience is always in flux and cannot be trusted.

Examples of rationalism in everyday life

We usually apply reason as the main source of knowledge in the following scenarios:

  • When solving any mathematical operation. There we make exclusive use of reason.
  • Deduce that the alternation between day and night is due to the rotational movement of the earth on its own axis.
  • Know that the formation of hurricanes is due to a natural method of the earth to balance its temperature, which occurs in certain areas of the planet and not in others.
  • Deduce that tides are produced by gravitational force exerted by the moon on the earth.

As we can see, to achieve such knowledge, the exercise of reason was necessary. Well, with only the evidence we would have stayed in the phenomena without delving into or analyzing their ultimate causes.

Mathematics is intimately linked with rationalism.

A posture that contributed to knowledge

Rationalism was a philosophical movement that not only placed the problem of knowledge among the main topics of discussion, but also brought up topics such as the relationship between body and mind or the nature of passions and freedom. These are still the subject of interesting philosophical reflections.

Furthermore, by defending the self-sufficiency of human reason to explain reality, contributed to placing the subject in a privileged position vis-a-vis religious authority. Something that was prevailing throughout the Middle Ages.

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