Philosophical Perspectives on Reality and Knowledge

Foundations of Reality and Knowledge

Plato: Dualism and the World of Ideas

We can only attain certain knowledge through reason, which is eternal and unchanging (universal). Plato addresses the issue of mind-body dualism, asserting that the body is the prison of the soul. The World of Ideas cannot be known by the senses. The senses are linked to the body and are unreliable, but the soul possesses an immortal faculty—reason—which allows it to perceive the World of Ideas.

Plato's Two Worlds

• The Permanent World: The World of Ideas (accessible via reason).
• The Changing World: The World of the Senses (accessible via the body).

René Descartes: Rationalism and Methodical Doubt

Descartes, a rationalist, introduced a new method for philosophical reflection based on a fundamental principle: doubt (duda). This doubt is applied to everything except the personal conviction that “I am thinking.” On this basis, he discusses the relationship between the mind and the world.

Descartes maintains a dualistic vision, considering two fundamentally different types of substances: Res Extensa (material) and Res Cogitans (immaterial). The body belongs to the material group, governed by the same mechanical laws that govern the universe (seen as a machine). The soul, characterized by thought, feeling, and will, belongs to the immaterial group.

Soul and body are independent realities that communicate via the pineal gland, which Descartes believed existed in the brain.

The Cartesian Substances (Res)

• Substance Infinite: God
• Substance Thinking (Res Cogitans): The Soul (Alma)
• Substance Extended (Res Extensa): Matter

Immanuel Kant: Limits of A Priori Knowledge

Our knowledge is limited to the representations of things constructed through the collaboration of a priori ideas provided by reason. These ideas do not originate from experience; they are innate and permanent. The world becomes a reality built by the subject from empirical intuition.

Kant distinguishes between the phenomena (the reality constructed by our intuition) and the “thing-in-itself” (Ding an sich), which remains unknowable. Kant defines metaphysics by stating that we must accept the use of reason within the structure of knowledge, but we must limit its possibilities in relation to the world; we cannot go beyond the bounds of possible experience.

Materialist Metaphysics

Materialist theories explain the foundation of reality based solely on sense data. They accept that human knowledge is limited but maintain that we are capable of understanding a complex and changing world.

Key Materialist Thinkers

• Presocratics: Democritus

  Argued the atomistic theory: there are only atoms and void. Bodies are aggregates of atoms formed by collisions in a vacuum, and everything is governed by chance.

• Modern Materialism: La Mettrie

  Views the human being as a complex mechanism where there is no room for spiritual substance.

• Marxist Materialism: Karl Marx

  All reality is resolved in matter. Everything, including history and current social phenomena, is explained from the material field.

Defining Truth

The concept of truth is crucial, serving as a pillar for the rule of law and scientific research.

• Ontological Truth: Truth concerning being (ontos), the reality of essence.
• Epistemological Truth: Truth concerning contents, propositions, or knowledge.