It is all in the Optimization Function

At one of the meetups on data science I recently attended, a question about when AI would reach the level of human thinking was posed. I was surprised to see people raising hands in response to a year of 2030, 2045, 2065, … I did not raise my hand at all because I don’t believe it will happen. Ever.

Am I naive? Ill-informed? No, I would like to think not. I totally respect the fact that human brain’s wiring is simple, and boils down to fat, water and electricity. We think we are smart, but we really aren’t. A computer program can be written to mimic us. Several successful examples already exist. We are easily fooled by such examples and attribute more intelligence and feelings to them than we ought to. I myself briefly thought that the two robots that were programmed to “look out” for each other by Tufts University research team really do care about one another. Their cute voices had something to do with it. The robots are driven by some optimal reward function, and they are programmed to optimize it. The robots don’t care about each other. True universal care is too broad to be “coded-up”.

Cat Pictures Please is a great short science fiction story written by Naomi Kritzer. It is written as an inner monologue of an AI system that was developed to help people out. I like this story for two reasons. Firstly, it is a good example of the most basic difference between humans and AI – we are lazy, irrational and slow. The AI system is logical, methodical and fast. Secondly, it highlights what is at the core of all AI – a reward or a payoff that must be optimized. In Cat Pictures Please a part of AI’s reward somehow becomes pictures of cats… If a robot works out that charging itself generates the greatest long-term reward it will end up charging itself most of the time. Note, I am writing ‘works out’, but I really mean converges onto. If humans are mostly composed of fat, water and electricity, the AI is down to search and optimization function.

Searching is what evolutionary computing, reinforcement learning, gradient descent/ascend (thus pretty much all types of regression) and unsupervised learning is about. Minimizing some cost function or alternatively optimizing a reward function is what can make an AI system “happy”. Both must be accurately programmed to work. Undeniably, many functions can be automated and perfected with searching for the best reward approach. Thus many things are within the AI’s reach. I am not saying that if autonomous weapons are unleashed upon us,  we are going to be just fine. But what I do believe in is that AI will never be able to truly think like us. It will never be able to act and rely on luck or its gut feeling. It will never be able to demonstrate such degree of delusion that its bluffing can achieve results, as humans can. AI will never become superstitious, doctrinal and lazy. Even if AI will one day become genius, it won’t reach human’s highs of stupidity. Since as Albert Einstein once said, the difference between stupidity and genius is that genius has its limits.