Tag Archives: knowledge

Evidence: A Definition and Example

There was a discussion of the concept of evidence on one of the forums I post to, so I posted the following analysis.

Evidence is a body of observations that have been logically integrated to their cause. I will give an illustration using one of Jerry Coyne’s lines of evidence for the theory of evolution in Why Evolution is True.

According to Coyne, the species of animals found on islands near continents bear significant similarities to the animals on the mainland, but they differ from the animals on the mainland in ways that allow them to fill the specific niches available on the island, and the only species of animals found on the island are ones small enough to be blown by the wind or carried on driftwood to the island. Therefore, they must have been carried from the mainland to the island and evolved into a variety of new species once there.

Let’s take this apart into its components.

First, Coyne’s argument depends on observation. Scientists had to make countless measurements of species that live on islands near a continent and the species on the nearby mainlands to arrive at this conclusion. For example, in one case, they had to measure the beaks of birds on the island to show that they were adapted to eating nuts as opposed to the beaks of the birds on the mainland.

Second, Coyne’s argument integrates these observations. The observations are put together into a coherent whole that encompasses the fact that the species on the island are similar to the species on the mainland, the fact that there are specific niches on the islands that these species have adapted to fill, and the fact that the species on the island are all relatively small or have the ability to swim. These are all made part of a unified narrative.

Third, Coyne’s argument integrates these observations in accordance with logic. Coyne does not appeal to mysticism to explain the observations he cites, and he does not invent his explanation out of whole cloth. Rather, he logically infers the conclusion that is necessitated by the available facts.

Finally, Coyne’s argument logically integrates these observations to their cause. Causality is an entity acting according to its identity. Coyne’s argument reveals that the observations he cites are all manifestations of entities acting in an orderly fashion, according to their identities. The only entities that get to the islands are the ones that have the ability to do so due to their size or ability to fly or swim, and the only entities that survive on the islands are the ones that are adapted to fill the available niches, in obedience to causality.

I hope this has helped clarify the concept of evidence for you.

Introduction to Objectivist Epistemology: Chapter 1

In this post, I will summarize chapter 1 of Ayn Rand’s book, Introduction to Objectivist Epistemology. This chapter describes the stages a child goes through leading up to the ability to use concepts, as well as the basis for those steps in reality.

According to Rand, there are three stages that a child goes through:

First, the stage of sensations. Rand suggests that “an infant’s sensory experience is an undifferentiated chaos” which is forgotten by the time one becomes an adult. Adults can infer that they once experienced a sensation stage, but they cannot bring a sensation into their conscious awareness.

Second, the stage of percepts. Rand says “a percept is a group of sensations automatically retained and integrated by the brain of a living organism.” Adults are consciously aware of percepts, and they form the level at which we are directly aware of reality.

At the perceptual level, the child attains the (implicit, not yet explicit) concept of an existent, a thing that exists. This implicit concept develops through three sub-stages: “entity,” referring to the objects around him or her, “identity,” referring to the fact that he or she can distinguish these entities from the other things he or she sees, and “unit,” which refers to the fact that there are similarities and differences between these objects’ identities.

Rand next spends some time on the concept “unit.”

A unit is an existent regarded as a separate member of a group of two or more similar members. (Two stones are two units; so are two square feet of ground, if regarded as distinct parts of a continuous stretch of ground.) … Units are things viewed by a consciousness in certain existing relationships.

Rand points out that this concept allows us to extrapolate beyond our observations by defining a standard and thinking in terms of repetitions of the standard. I think what she has in mind here is primarily physics; physicists define a specific distance as the meter and then do physics in terms of repetitions or divisions of that standard meter. The point applies to any concept, though. For example, we can recognize more than one country as instances of the concept “country” because we can abstract from the specific number of people in the population, the specific geographic location, the specific system of government, etc. These are essentially just repetitions of the same thing, or of similar things we have seen elsewhere.

Summary in bullet points:

  1. Sensation stage
  2. Perceptual stage
    1. Existent
    2. Entity
    3. Identity
  3. Unit (Entry to conceptual stage)

Introduction to Objectivist Epistemology: Forward

Introduction to Objectivist Epistemology (ITOE) was Ayn Rand’s attempt to provide a foundation for her epistemology and, derivatively, the rest of her philosophy. In this post, I will summarize the forward of ITOE and comment on it.

In the forward, Rand repeatedly emphasizes the importance of the “problem of universals.” She takes the problem of universals to be the problem of what our concepts refer to in reality. For example, when I describe three men as “men,” what about those men am I referring to, if anything?

Why does Rand think that this problem is important? For one thing, since our knowledge is composed of concepts, the invalidity of concepts would entail the invalidity of all knowledge. If concepts are invalid, then there is no objective difference between mathematics and mysticism. She is probably also concerned about scientific methodology – if scientists don’t know where their concepts come from, then they might make conceptual mistakes without realizing it.

Rand lists four alleged solutions to the problem of universals that past philosophers have proposed: extreme realism, moderate realism, nominalism, conceptualism, and extreme nominalism. Rand expresses contempt for these solutions, but reminds the reader of the importance of the issue at stake for civilization.

It is worth noting that Rand introduces the problem of universals in roughly the same way the Internet Encyclopedia of Philosophy does:

Often we predicate properties of individuals. When we say that both cherries and rubies are red, for instance, we seem to say individuals share common properties, those that make cherries cherries, those that make rubies rubies, and those that make both red. Predicates are said of many subjects, then, but is there anything in reality to match the linguistic one-over-many? Are there general truths? Is there commonality in nature, in reality; or is commonality imagined and illusory, perhaps a mere product of language? If the latter, how can we accommodate the intuition that it is the world, and not our conventions, that make predications true or false? The Problem of Universals arises when we ask these questions. Attempts to solve this problem divide into three broad strategies: Realism, Nominalism, and Conceptualism. We’ll take these in turn, and consider the pros and cons of each.


Rand concludes by reminding the reader that she will be taking for granted the validity of the senses and the axiom that existence exists.

Response to Coyne on the Humanities

I wrote the following in response to this post on Jerry Coyne’s blog, Why Evolution is True. Coyne said, among other things, that “science is the only game in town if you want to ascertain what’s real in our universe,” and he seemed to base this partly on the failure of the humanities to reach consensus.

I’m majoring in computer science and philosophy. I have some thoughts on this.

If you ask a philosophy professor a philosophical question, then they will say “well, first what are all of the possible positions on this issue that don’t contain explicit contradictions, and how many ways can we divide those up? what did Kant say and is that the right interpretation of Kant, because heaven forbid we ignore what Kant said? I have an intuition that this and that are true, and my colleagues have all of these other intuitions and we have to juggle them all.”

By contrast, if you ask a computer scientist a question about computer science, then they will immediately defer to reality. They will run the program or do the math, regardless of what other computer scientists have said. Quicksort is accepted because it works when we run the program, not because it’s been accepted by some authority.

This is the difference between the sciences and the humanities, in my view. It’s not that the humanities can’t make progress, it’s just that the humanities have accepted toxic patterns of reasoning that inhibit progress. I can’t help noting, by the way, that Dr. Coyne’s example of postmodernism is a perfect illustration of my point here.

Originally, the concept of philosophy was awesome. The idea of developing a way of living that is based on facts is what draws a lot of people into studying philosophy in the first place. But I think that got corrupted at some point into a sterile academic exercise.