Another problem with the experience system, which must proceed from external reality, is that it cannot explain the diversity of our experience. We are in a system that gives us multiple and different experiences. While externalism gives us an explanation of why our experience is like this, it cannot give us an explanation of why our perception of these things is different. Thus, some externalist views argue that it is simply how differently we perceive things; others argued that different experiences could be explained on a more primitive or psychological level.
The philosopher William James developed an important doctrine to justify his view of the externalist theory of experience. This teaching is known as the law of similarities. James argued that each of us associates a stimulus with a certain object with which it has no physical connection, but is an object with which we can interact. We can imagine this object as having a different physical form or appearance than the object we originally responded to.
The similarity law is an explanation of why we perceive the world in this way. This explains why the externalist explanation of our experience of things does not work.
While the law of similarity itself is not a general explanation of how we perceive things, it explains why we are able to react to things differently from how we react to things that we encounter in the outside world. However, this does not explain why some people have different sensory experiences. This question has long been discussed in philosophy, but the most commonly proposed solution is related to cognitive abilities. One position is that the law of similarity explains why there are some people who do not perceive things in the same way as others. However, the hypothesis that this law is based on a general truth, the truth that explains why people do not see things the same way, is usually viewed as not supported by most philosophers. Instead, the main explanation suggested is that some of the differences in sensory experience can be explained on a more subtle level. For example, we may see an apple differently because of what we know about that apple. We know that the green apple was of the same species as the apple we see in front of us now, and therefore the differences in perception that we see are due to our knowledge.