Objective

Overview
Objectivity, in relation to evidence and the scientific method, is the existence of a thing outside of a mind. For instance, while the perception of music exists in a mind, and is thus subjective, the actual physical air vibrations exists outside of minds, and is thus objective. A third party can examine air vibrations, but cannot examine a person's perception of music.

Objectivity is a critical standard for evidence, because it maximizes accuracy in determining what's true.

Misinterpretations
Human understanding of the world around us needs to pass through several layers, from the objective reality, to the internal human mind.
 * Objective reality can take a form that can be mistaken for something else, such as mirages or optical illusions.
 * The human sensory, such as the eyes and ears, as imperfect biological devices, can incorrectly gather information. Grainyness of vision in the dark, or occasional neurons firing, causing flashes of light, are examples of this.
 * The human brain, as a powerful pattern recognition engine, can detect a false pattern. Ink blot tests and seeing sheep in clouds play on this phenomenon. It's important to note that the nature of our brains is to fill in the blanks with their best guesses, if information is lacking. That's why we often mishear what someone says in a noisy room. We're sure the other person said one word, when he/she actually said another.

By keeping the evidence objective, we can have multiple people examine the same object, cross examine, and reduce the chances that the first person simply misunderstood what he/she perceived.

The primary way that apologetics fails in this regard is that a lot of the "evidence" they posit are 'only in the mind. There's no way for anyone else to examine the object, and since we only have this person's word on his/her evidence, we cannot then exclude other possibilities, such as that it's simply a delusion on his/her part.

A good example is the perception of design, as an apologist might say:


 * I look at nature and I perceive design, like I can perceive that a watch is designed, therefore, I can infer design. Thus, the evidence that nature is designed is that it appears to be designed.

There's no way to tell whether this opinion isn't just all in his/her head. It would be like saying:


 * ''I look at this object and I perceive that it's a cube, like I can perceive that dice are cubes, therefore, I can infer that it's a cube. Thus, the evidence that the object is a cube is that it appears to be a cube.

No one is going to take that argument seriously, because the first question is going to be, "How can you tell whether something is a cube or not?" Luckily, we do have a description that is objective, and can be objetively confirmed:


 * A cube is a geometric shape with 6 sides that are all the same size and shape, which are 4-sided polygons, where the edges are at 90 degree angles to one another.

The perception of design is all in the apologist's head, as we have a very vague definition of how one can tell if something is designed, whereas we can accurately and objectively verify that an object is actually a cube.

Other forms of subjective evidence that is basically useless for convincing anyone else is:
 * Feeling that something is true.
 * Personal experiences that only the claimant has any access to the information.

Diminishing Returns
While we, as thinking beings, will always have to deal with a subjective layer of error, as described in misinterpretations, the error can compound unless we have an original to examine. We don't know whether we're perceivng something in the supposed original, or in a copy of the original. This is why heresay is not accepted in the U.S. justice system. By the time we get the information of what Bob says that Fred says about what Jack said that Jill did, the data is simply too unreliable to be useful.

Objective evidence, such as having an original fossil to examine, bypasses the problem of diminishing returns, and greatly minimizes the potential for subjective error accumulation.

Bias
Even if reality doesn't "trick" us, our sensory organs don't fail, and our perceptions and interpretations are fairly accurate, yet another layer of error exists for subjective evidence - bias.

An imporant thing to know about brains is that they are very adept at information management. Without realizing it, our brains sift through an incomprehendable amount of data entering our senses, and on-the-fly, filters that information into categories, and for bulk of that data, discards it. While the metrics for which data is determined to be discarded (or retained) varies from person to person, a very general metric is whether it fits our current understanding of the world around us.

This is a common phenomenon that manifests with our minds. Some forms of this are confirmation bias and cognitive bias in general.

While the individual peices of evidence that builds one's understanding of the world might be objective, the understanding itself is often used as a basis of evidence, and can be subjectively inaccurate, especially if they're based on a priori beliefs about reality.

An excellent example of this is the supposed veracity of prayer.
 * 1) Prayer is believed to work.
 * 2) Any answered prayer is mentally retained as confirmation that prayer works, and then remembered.
 * 3) Any unanswered prayer is discarded as a fluke, or dismissed for other ad hoc rationalizations, and then forgotten.
 * 4) A subjective understanding about the veracity of prayer forms in a person's mind based on bias sample sets.
 * 5) This aggregated information is then personal evidence for the fact that a prayer-answerer (God) exists.
 * 6) Therefore, God exists.

Despite that this person collected objective data, subjective statistical evidence was derived from that, evidence that we cannot examine objectively and confirm. It's possible that the prayers were in fact answered, and now that we are testing prayer after the fact, the god stops answering the prayers. We would then have to take the person's word for it, in order to accept the claim.