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Complex Simplicity: The Fallacy of Occam's Razor EXEMPLAR
Topic: Occam's razor
by Sophie, 2020 Cohort
Attributed to English friar William of Ockham, Occam’s razor is, quite simply, the fundamental principle of simplicity. Based on a desire for philosophical parsimony, it states that “plurality is never to be posited without necessity.” More simply, this means that when presented with two competing theories, all else equal, the simpler option is the better option. When looking at a complex problem, therefore, Occam’s Razor is useful in its ability to eliminate improbable options in order to focus on key elements of the problem and find less convoluted solutions.
Occam’s razor, however, is also somewhat of a fallacy. A key tenant of the theory lies in the psychology and mental models of humans. According to the simplicity principle, our minds prefer to perceive everything in the simplest possible form. Simplicity, however, is a highly subjective notion. Whilst one person, who is a whiz at maths, may think that Pythagoras’ theorem is a straightforward explanation for why the sum of two sides of a right angle triangle equal the square of the hypotenuse, to others, this is nonsense and as far from a simple explanation as possible. Hence, it is up to each individual to interpret the simplicity of each event. Further, and perhaps more importantly, there is simply no evidence that simplicity = truth. To say that simplicity leads to greater accuracy, therefore, is highly controversial.
Another way to understand this fallacy is through Daniel Kahneman’s System 1 and System 2 thinking. System 1 is ruled by our automatic and unconscious thinking- our mental models. System 2, however, is a slower, more controlled and analytical method of thinking- one where reason
Consider these ways of thinking in terms of Flat Earth theory. When we look at the horizon, the Earth looks flat. Taking away any logic and reasoning, System 1 then dictates that the Earth is then in fact flat. That is the simple answer. By this logic, we only have to worry about a single plane and simple geometry to calculate distances and angles, which further appeals to instincts. Scientifically though, we know that this is not the case- the horizon only appears flat to the human eye due to its enormous diameter in relation to our tiny vantage point at any given time. This is where System 2 thinking kicks in. Despite the fact that our intuition suggests a simpler answer with less external factors, science, logic and reasoning prove this answer to be false. To erroneously apply Occam’s Razor in this context therefore leads us to a wildly factitious
That being said, the benefits of simplicity cannot be completely ignored. Without System 1 thinking and the simplicity offered by Occam’s Razor, we would lose the ability to make fast judgements and direct everyday behaviour. When it comes to complex decision-making, however, we must first use System 2 to make rational, evidence-based decisions. Only once all evidence has been considered and two or more competing theories emerge could Occam’s Razor then be applied.
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Attributed to English friar William of Ockham, Occam’s razor is, quite simply, the fundamental principle of simplicity. Based on a desire for philosophical parsimony, it states that “plurality is never to be posited without necessity.” More simply, this means that when presented with two competing theories, all else equal, the simpler option is the better option. When looking at a complex problem, therefore, Occam’s Razor is useful in its ability to eliminate improbable options in order to focus on key elements of the problem and find less convoluted solutions.
Occam’s razor, however, is also somewhat of a fallacy. A key tenant of the theory lies in the psychology and mental models of humans. According to the simplicity principle, our minds prefer to perceive everything in the simplest possible form. Simplicity, however, is a highly subjective notion. Whilst one person, who is a whiz at maths, may think that Pythagoras’ theorem is a straightforward explanation for why the sum of two sides of a right angle triangle equal the square of the hypotenuse, to others, this is nonsense and as far from a simple explanation as possible. Hence, it is up to each individual to interpret the simplicity of each event. Further, and perhaps more importantly, there is simply no evidence that simplicity = truth. To say that simplicity leads to greater accuracy, therefore, is highly controversial.
Another way to understand this fallacy is through Daniel Kahneman’s System 1 and System 2 thinking. System 1 is ruled by our automatic and unconscious thinking- our mental models. System 2, however, is a slower, more controlled and analytical method of thinking- one where reason
Consider these ways of thinking in terms of Flat Earth theory. When we look at the horizon, the Earth looks flat. Taking away any logic and reasoning, System 1 then dictates that the Earth is then in fact flat. That is the simple answer. By this logic, we only have to worry about a single plane and simple geometry to calculate distances and angles, which further appeals to instincts. Scientifically though, we know that this is not the case- the horizon only appears flat to the human eye due to its enormous diameter in relation to our tiny vantage point at any given time. This is where System 2 thinking kicks in. Despite the fact that our intuition suggests a simpler answer with less external factors, science, logic and reasoning prove this answer to be false. To erroneously apply Occam’s Razor in this context therefore leads us to a wildly factitious
That being said, the benefits of simplicity cannot be completely ignored. Without System 1 thinking and the simplicity offered by Occam’s Razor, we would lose the ability to make fast judgements and direct everyday behaviour. When it comes to complex decision-making, however, we must first use System 2 to make rational, evidence-based decisions. Only once all evidence has been considered and two or more competing theories emerge could Occam’s Razor then be applied.