Evolutionary Explanations: From Creationism to Darwinism
1. Creationist Explanations
Creationist explanations attribute the origin of humanity to a literal interpretation of the Book of Genesis. Key tenets include:
- God created all living species separately and definitively.
- God created man in His image and likeness.
These concepts align with “fixism,” the belief that species are immutable over time. Fixism acknowledges the adaptability of individuals to their environment, often attributing it to intelligent design. However, this adaptability remains within the species, without giving rise to new species.
In the eighteenth century, prominent proponents of fixist creationism included Carl Linnaeus (1707-1778) and Georges Cuvier (1769-1832). Cuvier is regarded as the father of paleontology and comparative anatomy.
2. Darwinian Evolutionary Explanations
The publication of Charles Darwin’s Origin of Species in 1859 challenged fixist doctrines. Darwin’s theory, which forms the basis of modern evolutionary explanations, can be summarized as follows:
- Species undergo continuous and gradual transformations.
- Natural selection drives evolution.
According to natural selection, spontaneous changes occur within species, and only the most effective adaptations for survival endure. Individuals best suited to their environment have a higher likelihood of survival, reproduction, and passing on their characteristics hereditarily. This implies that humans descended from now-extinct primates.
However, Darwin’s theory did not explain the mechanisms of hereditary transmission. Gregor Mendel (1822-1884) addressed this gap. Seven years after the publication of The Origin of Species, this Augustinian friar (the father of modern genetics) formulated a theory of inheritance. He proposed that characteristics of living beings are determined by what he called genes, and that changes in these characteristics arise from alterations or mutations in the genetic material.
Key Philosophical Principles
Principle: A fundamental concept from which something originates, becomes, or is understood. Principles include nature, elements, premises, purpose, substance, and cause.
Cause: The reason for something’s existence or occurrence. It’s the “why” of everything. There are four types of causes:
- Material Cause: The matter from which a thing is produced.
- Formal Cause: The form or essence of a thing.
- Efficient Cause: The entity that initiates the becoming.
- Final Cause: The purpose or direction of change, leading to the perfection of being.
Nature: The principle and cause of motion and rest within something, inherently and not accidentally. Matter and form constitute nature, with form being primary.
Ente (Being): That which exists, either inherently or accidentally (within a subject), whether actual or potential.
Substance: The subject that is not predicated of another, and the separable form or kind of everything.
Accident: Anything inherent in something but not part of its substance.
Perfection: Actuality. Everything is understood in relation to its actuality. Form is the actuality of matter.
Subject: The primary subject of all things, from which something originates or becomes, not accidentally.
Terms: What defines the limits of something.
Form: The disposition that determines the substance in its nature. It can be substantial or accidental.
Movement: The act of being in potentiality, as it is in potentiality. Imperfect measure of the imperfect. Operation is distinguished from act: act of perfect perfect.