What Technical Analysis Assumes

Units 2 and 3 taught you to value a business by studying the business itself. Technical analysis takes a completely different angle. It largely ignores what a company does and studies only the behavior of its price and trading volume, on the belief that the chart itself contains useful information about where the price may go next. Before learning any of its tools, you need to understand the assumptions it rests on, and to understand them with clear eyes, because they are genuinely debated.

The three classic assumptions

• The market discounts everything: technical analysts assume all known information, about fundamentals, the economy, and sentiment, is already reflected in the price. If that is true, studying the price alone is enough, because the price already embodies what participants know.
• Prices move in trends: the second assumption is that prices tend to move in identifiable trends that persist for a time rather than wandering randomly, and that a trend in motion is more likely to continue than to reverse until clear evidence says otherwise.
• History tends to repeat itself: the third assumption is that recognizable patterns recur over time because they are driven by human psychology, and human responses to greed and fear are reasonably consistent across eras.

Probabilities, not certainties

On its own terms, technical analysis deals in probabilities, not guarantees. A pattern or signal is understood to shift the odds, not to dictate an outcome. Every signal fails some of the time, which is exactly why the risk management covered later in this unit is the core of the whole approach.

The honest caveat

You should know that the foundational assumption, that past prices help predict future prices, is directly challenged by a major idea in academic finance: the efficient market hypothesis, which Unit 10 examines in depth. In its weak form, this hypothesis argues that past price movements cannot be used to earn excess returns, because any predictable pattern would be traded away. The academic evidence on technical analysis is mixed, and much of it is skeptical. Some studies find modest effects, and many find that apparent patterns do not survive rigorous, out-of-sample testing once trading costs are included.

Technical analysis is a lens, not a crystal ball. Learn its tools, but hold its claims with the skepticism that good evidence demands.

A self-fulfilling element, and a balanced view

One reason some technical levels seem to matter is partly self-fulfilling. If enough traders watch the same level and act on it, their collective behavior can make the level real, at least temporarily. That is a behavioral mechanism, not a law of nature. The balanced view is this. Technical analysis is widely used by real market participants, so understanding it helps you read what others are watching and reacting to. At the same time, it is not a proven science, and the honest analyst treats it as one framework among several, leans on risk management, and stays wary of seeing patterns that are not really there. Technical and fundamental analysis are not mutually exclusive, and many practitioners use price action for timing while relying on fundamentals for what to own.

With clear eyes about what technical analysis assumes and where it is debated, we can start learning its tools. The first practical skill is reading the basic unit of most charts: the candlestick.