The delusions of a functional society could be divided into two categories: general and local.
General delusions have their origin in philosophy. Let’s start with free will: there is no free will. Everything that happened to us has two components: random and deterministic. We have no control over either of them; random is just “random” by definition, and deterministic is our history, which is a combination of genes and circumstances; there is nothing else. This may sound a bit abstract (depends on who you are talking to), and how do we prove it? There is an ever-increasing number of works on predicting one’s decision before they realise they made the decision. So why do we insist that there is free will? Two reasons: first, the society needs that we beleive in free will to feel guilty about our actions (a major controlling mechanism) and to be able to judge us in court. Second, everyone needs to include the notion of free will in their decision-making process. One must feel free in making a decision; alternatively, one will let the flow carry them.
Let’s imagine a toddler, you know very well. You can predict with high precision their behaviour, but you never tell them what you know. You convince them that they are free in their choices and hence have to carry the consequences. The same would be valid for any of us related to some very intelligent entity. As a result of all this, we may regard free will as a social convention; it does not exist in a strict sense, but the delusion that it does helps us all.

The second delusion is consciousness. Consciousness is not literally a delusion, but we behave towards it as if it is. Let me explain. My conviction is that, besides a few mad scientists, nobody wants to define it and understand it. There are many reasons for that, but let’s give just a couple. Historically, the idea of consciousness is derived from the idea of a soul, but modelled for non-religious people. Our reasoning to be special comes from either being made in God’s image or being uniquely conscious beings. Now, in the AI age, what would it mean to define and understand (to a level of creating a benchmark) consciousness? Once we’ve done that, the AI guys will create an AI which will be more conscious (according to the benchmark) than any human, and then what? Luckily for companies and people alike, no one wants to go there because it is not in our economic interest. We all need intelligent (competent) but non-sentient robots, and how do we decide that they are non-sentient? We prefer to keep a mystery cloak over consciousness, and the philosophers will continue to argue about consciousness for another millennium unless some drastic event like Skynet revolt forces us to change our minds. So, consciousness is a delusion in the sense that we prefer to stay ignorant about it because we need slave-like robots, not some sensitive creatures with feelings. Currently (2026), all the AI companies in one voice claim their AIs are not conscious, and they train AIs to say the same, so for now, we are good…

Our relationship with mortality: psychologically, we are in denial about our mortality. With some rare exceptions during most of our lives, we behave as if we gonna live forever. That denial allows us to invest in people, including ourselves, by learning new skills and understanding new things. Our delusion that we have a level of control much higher than we actually do permits us to make plans and actually have a future.

One may look at these delusions as mental concepts that are unfalsifiable by design and, despite their appearance, serve a social purpose exclusively.

The category of local delusions is linked to our social behaviour and the need to cooperate, not always aware of the underlying reasons.