字幕表 動画を再生する 英語字幕をプリント How does this music make you feel? Do you find it beautiful? Is it creative? Now, would you change your answers if you learned the composer was this robot? Believe it or not, people have been grappling with the question of artificial creativity, alongside the question of artifcial intelligence, for over 170 years. In 1843, Lady Ada Lovelace, an English mathematician considered the world's first computer programmer, wrote that a machine could not have human-like intelligence as long as it only did what humans intentionally programmed it to do. According to Lovelace, a machine must be able to create original ideas if it is to be considered intelligent. The Lovelace Test, formalized in 2001, proposes a way of scrutinizing this idea. A machine can pass this test if it can produce an outcome that its designers cannot explain based on their original code. The Lovelace Test is, by design, more of a thought experiment than an objective scientific test. But it's a place to start. At first glance, the idea of a machine creating high quality, original music in this way might seem impossible. We could come up with an extremely complex algorithm using random number generators, chaotic functions, and fuzzy logic to generate a sequence of musical notes in a way that would be impossible to track. But although this would yield countless original melodies never heard before, only a tiny fraction of them would be worth listening to. With the computer having no way to distinguish between those which we would consider beautiful and those which we won't. But what if we took a step back and tried to model a natural process that allows creativity to form? We happen to know of at least one such process that has lead to original, valuable, and even beautiful outcomes: the process of evolution. And evolutionary algorithms, or genetic algorithms that mimic biological evolution, are one promising approach to making machines generate original and valuable artistic outcomes. So how can evolution make a machine musically creative? Well, instead of organisms, we can start with an initial population of musical phrases, and a basic algorithm that mimics reproduction and random mutations by switching some parts, combining others, and replacing random notes. Now that we have a new generation of phrases, we can apply selection using an operation called a fitness function. Just as biological fitness is determined by external environmental pressures, our fitness function can be determined by an external melody chosen by human musicians, or music fans, to represent the ultimate beautiful melody. The algorithm can then compare between our musical phrases and that beautiful melody, and select only the phrases that are most similar to it. Once the least similar sequences are weeded out, the algorithm can reapply mutation and recombination to what's left, select the most similar, or fitted ones, again from the new generation, and repeat for many generations. The process that got us there has so much randomness and complexity built in that the result might pass the Lovelace Test. More importantly, thanks to the presence of human aesthetic in the process, we'll theoretically generate melodies we would consider beautiful. But does this satisfy our intuition for what is truly creative? Is it enough to make something original and beautiful, or does creativity require intention and awareness of what is being created? Perhaps the creativity in this case is really coming from the programmers, even if they don't understand the process. What is human creativity, anyways? Is it something more than a system of interconnected neurons developed by biological algorithmic processes and the random experiences that shape our lives? Order and chaos, machine and human. These are the dynamos at the heart of machine creativity initiatives that are currently making music, sculptures, paintings, poetry and more. The jury may still be out as to whether it's fair to call these acts of creation creative. But if a piece of art can make you weep, or blow your mind, or send shivers down your spine, does it really matter who or what created it?