>our brain responds and tries to find out what it means.

>This stimulus-response model separates our inner subjective world from an outer objective world. We can never know for sure what is going on objectively. There is no meaning in the world,

[Emphasis added.]

This passage reveals an ambiguity in the use of the word "mean"/"meaning" which demonstrates an internal inconsistency, a self-contradicting premise, in the author's reasoning and source material.

As an analogy, the contrast between 'stimulus-response' and 'affordance' models can be instructive in grappling with philosophical paradigms concerning consciousness and existential metaphysics. As an example, it is, if you will forgive the word, meaningless. Animals are also using visual systems comprised of not just eyes, but heads and bodies and ground, no more or less than we do. But animals do not spend thousands of years developing technological engineering projects like text and the Internet to discuss these things. So in terms of being informative about the human condition or what meaning is, I believe there is a good reason why Gibson's book from the 1970s has faded into obscurity, as it doesn't actually provide any explanatory ideas, it simply covers the same ground ancient philosophers did and circles the same drain of existential uncertainty. The essay rightly observes that Gibson's more comprehensive analogy has been cited and used by many designers and architects, but it isn't like buildings or smartphone interfaces provide any meaning in our lives. The observation that the form of an artificial object should communicate its function does not rely on this book or Gibson's analysis.

Meaning does not derive from constructing models of the external world, or the internal world for that matter, which afford us survival advantage. It relates to the explanatory power of those models for non-utilitarian purposes, not the accuracy of the models themselves. We do not invent meaning, we observe it, and yet we are the only creatures (biological objects) capable of observing it. To say "we can never know for sure what is going on objectively" denies that there is any value in the affordable model, and Gibson's perspective admits as much by reducing the goal of that model to the same limitations of a stimulus-response system: physical survival. From a human perspective, simply surviving is not meaningful, it is the very absence of meaning. A philosophy which equates "meaning" with "what it can afford us" is a pitiful lack of philosophy which denies the existence of "meaning" to begin with.