Philosophical Critiques of Truth and Knowledge

Nietzsche's Critique of Science and Objective Truth

Nietzsche argues that, like philosophers, scientists often overestimate their intellectual capacity. He posits that truth and lies are social conventions.

He accuses scientists of equating objectivity with the use of reason and knowledge while deliberately excluding sensitivity and emotion. For Nietzsche, words and concepts, when used as abstractions, become inadequate to express life itself.

The pretense of achieving a singular, objective truth is an impossible creation; truth is fundamentally individual. Human scientific knowledge offers schemes, but not reality itself. Mathematics and logic are activities of relationship that have nothing to do with reality.

Nietzsche's Assertions on Truth and Science

1. Sometimes lies are as useful as the truth, even profitable and beneficial.
2. The will to truth held by scientists is useless and even dangerous, like any absolute attitude.
3. The basic attitude underlying science is the fear of life and the fear of becoming—a refusal to accept that nothing is fixed, stable, or safe to hold onto.

Plato's Ethical Intellectualism

Plato defends moral intellectualism, asserting that virtue is wisdom. He who knows what is necessary to act well will act justly. Moral excellence is achieved through knowledge and subsequent purification.

The Virtues of the Soul in Plato's Republic

Plato considers Justice as the supreme virtue of the soul in the Republic. Justice within the soul is defined by the proper coexistence and harmony between its three parts:

• The Rational Part: Must be prudent (wisdom) to address the world of Ideas to which it belongs and properly guide the irrational parts.
• The Irascible Part: Corresponds to Fortitude (courage).
• The Appetitive Part: Corresponds to Temperance (moderation).

Saint Thomas Aquinas: Man and Knowledge

Saint Thomas Aquinas (following Aristotle) understands the human being as a unit composed of a material substance (the body) and a form (the soul). He distinguishes three kinds of soul: rational, sensitive, and vegetative.

Aquinas maintains that the soul is immortal, specifically the rational part, which he calls the Active Intellect, capable of making abstractions.

Two Kinds of Knowledge

1. Sensible Knowledge

   The human being captures reality through the senses. Thanks to imagination, the senses form an image of reality in the human mind, which is called a phantasm (or sensible image).

2. Abstract Knowledge

   Understanding performs two key operations:

   1. The abstraction performed by the Agent Intellect.
   2. The formation of universal concepts by the Possible Intellect.