That dream about the dinosaur on the leotard. Those times that you said that thing that you know you shouldn't have said, or even that thing you didn't even know you were gonna say. The little cogs of your consciousness cranking away, making your life possible, making society function all of the things that you're so glad you can do, and all of the ones you wish you could stop doing. Excluding other human minds, your mind is the most complicated piece of the universe that humans currently know about. The rules that govern it are mysterious and elusive. Maybe our brains just aren't complex enough to understand themselves, but that's not gonna stop us from trying. The word psychology comes from the latin for the study of the soul, and while its formal definition has evolved over the last several decades, today we can safely call it the science of behavior and mental processes. The term psychology wasn't coined until around the turn of 16th century, and a practice that we would call science today wasn't established until the mid 1800.

But of course, humans have always been curious about themselves and what's going on up here. Aristotle pondered the seed of human consciousness and decided that it was in the heart, not the head, being as we have seen quite a lot here on crash course, absolutely and completely wrong. 2000 years ago, Chinese rulers conducted the world's first psychological exams requiring public officials to take personality and intelligence tests. And in the late 800, Persian doctor Mohammed ibn Zakaria al Razi, also known as Rasis, was one of the first to describe mental illness, and even treated patients in what was essentially a very early psych ward in his Baghdad hospital. From the efforts of those early thinkers up until today, the field of psychology has been all about tackling some of the big questions. How can humans do horrible things like commit genocide and torture other humans, and how come we know those things are horrible? Do we have free will or are we simply driven by our environment, biology, and nonconscious influences? What is mental illness and what can we do about it? And what is consciousness or the notion of self? If I lose my awareness of myself, am I still human? I don't know. But over the next 6 months, these are the questions that we're gonna be exploring together. How our brains work, how they can break, how they can be healed, why we behave the way we do even when we don't want to, and what it means to be thinking and feeling and alive.

When hearing the word psychology, most people probably think of a therapist listening to a patient unpacking the details of his day while reclining on a couch. Maybe that therapist is wearing glasses, chewing on a cigar, stroking his whiskered chin. Admit it, if you're thinking about psychology, you're probably picturing Freud. Sigmund Freud was one of the most tremendously influential and controversial thinkers of his time, maybe of all time. His theories helped build our views on childhood, personality, dreams, and sexuality, and his work fueled a legacy of both support and opposition. His life was long and spanned an important swath of history from the American Civil War to World War 2. But like most great scientists, Freud developed his revolutionary ideas by building on the work of others. And of course, innovation in the field didn't stop with him.

In truth, psychology is one of the most wildly diverse sciences in terms of the questions it proposes, the methods it applies, and the different schools of thought and disciplines it contains. Perhaps more than any other science, psychology is just a big old integrated melting pot. For instance, right around Freud's time, there were a lot of different schools of thought about how the study of the human mind should be tackled. Mainly, there were the ideas of structuralism, functionalism, and psychoanalysis. Scientific psychology got its start in 18/79 in Germany when physician Wilhelm Wundt set up the first psychology laboratory at the University of Leipzig just a few years after publishing his Principles of Physiological Psychology, considered the first true psychology textbook. Lundt and his student, Edward Bradford Titchener, took cues from chemists and physicists, and argued that if those people could break down all matter into simple elements or structures, why couldn't they do the same for the brain? They tried to understand

the structures of consciousness by getting patients to look inward,

asking them of consciousness by getting patients to look inward, asking them how they felt when they watched a sunset, or smelled a coffee, or licked a kitten, or whatever. Titchener named this approach structuralism, but despite its rigid sounding name, it really relied so much on introspection that it became too subjective. I mean, you may sense and feel something became too subjective. I mean, you may sense and feel something different than I do, even if we lick the same kitten. Psychologists, of course, can't actually observe a patient's inner thoughts or feelings, so ultimately the structuralist school of thought is fairly short lived. By contrast, American physician and philosopher William James proposed a different set of questions focusing on why we think and feel and smell and lick or whatever. Basically, he focused on the function of behavior. This approach, functionalism, was inspired by Charles Darwin's idea that adaptive behaviors are conserved throughout the evolutionary process.