and speech is ever-changing, supports Vygotsky's claims. Vygotsky's theory claims that thought and speech have different roots. And at the age of two, a child's thought and speech collide, and the relationship between thought and speech shifts. Thought then becomes verbal and speech then becomes rational. According to the theory behind cognitive therapy, founded by Aaron T. Beck, our emotions and behavior are caused by our internal dialogue. We can change ourselves by learning to challenge and refute our own thoughts, especially a number of specific mistaken thought patterns called "cognitive distortions". Cognitive therapy has been found to be effective by empirical studies. In behavioral economics, according to experiments said to support the theoretical availability heuristic, people believe events that are more vividly described are more probable than those that are not. Simple experiments that asked people to imagine something led them to believe it to be more likely. The mere exposure effect may also be relevant to propagandistic repetition like the Big Lie. According to prospect theory, people make different economic choices based on how the matter is framed. Studies concerning the Sapir-Whorf Hypothesis Counting Different cultures use numbers in different ways. The Munduruku culture for example, has number words only up to five. In addition, they refer to the number 5 as "a hand" and the number 10 as "two hands". Numbers above 10 are usually referred to as "many". Perhaps the most different counting system from that of modern Western civilisation is the "one-two-many" system used by the Pirahã people. In this system, quantities larger than two are referred to simply as "many". In larger quantities, "one" can also mean a small amount and "many" a larger amount. Research was conducted in the Pirahã culture using various matching tasks. These are non-linguistic tasks that were analyzed to see if their counting system or more importantly their language affected their cognitive abilities. The results showed that they perform quite differently from, for example, an English speaking person who has a language with words for numbers more than two. For example, they were able to represent numbers 1 and 2 accurately using their fingers but as the quantities grew larger (up to 10), their accuracy diminished. This phenomenon is also called the "analog estimation", as numbers get bigger the estimation grows. Their declined performance is an example of how a language can affect thought and great evidence to support