In Cognitive Personality Theory, we categorize people as extraverts or introverts based on whether they are cognitively reactive or proactive:

• Extraverts thrive in chaotic, ever-changing environments. They are reactive, tuning into situations and improvising on the spot.
• Introverts dislike chaos. They deal with it by making it predictable. They are proactive, anticipating and preparing for situations.

Ideally, everyone would always make optimal decisions with complete knowledge. However, understanding new situations takes time and effort. Te (Extraverted Thinking) and Ti (Introverted Thinking) approach this differently:

• Extraverted Thinking gains truth through hindsight, learning from experiences.
• Introverted Thinking attains truth through foresight, anticipating and planning for the future.

Understanding the world helps us survive and thrive. Humans are naturally curious, always seeking the elusive truth. As we learn more, we realize how much we don't know, pushing us to explore further. Thinking functions drive this quest for knowledge, helping us solve mysteries, achieve goals, and innovate.

Hindsight Thinking: Accumulating Experience
Te relies on reacting to present situations with available information. It’s about making swift decisions based on evidence at hand and refining those decisions over time.

• Example: "If it looks like a duck and quacks like a duck, it's a duck." Te trusts the current evidence and acts accordingly.
• Learning Process: Te users gather relevant information quickly, act, and then learn from those actions. Their decision-making accuracy improves with experience.
• Adaptability: Te users are agile and efficient, refining their approach with each new experience. They may seem quick to judge, but are constantly learning and adapting.

Foresight Thinking: Simulating Scenarios
Ti focuses on understanding and anticipating situations to avoid chaos.

• Example: "It's not always true that an animal that sounds like a duck is actually a duck." Ti users seek deeper insights beyond immediate evidence.
• Learning Process: Ti users gather data and analyze it thoroughly before acting. This cautious approach aims for precision and accuracy.
• Preparation: Ti users plan extensively, practicing and rehearsing to prepare for real-life situations. They strive to predict and avoid mistakes.

Most people use a mix of Extraverted and Introverted Thinking, but to understand these functions better, it's helpful to look at their extremes. We can see this more in Lens dominant (or Perceiving) types like ESFPs and INFJs since they tend to use one function or the other more dominantly, and therefore have a “purer” Thinking function.

For example, ESFPs primarily use Te execution, making them action-oriented and known for their go-getter attitude. While INFJs primarily use Ti modeling, focusing on understanding how systems or people behave. The employment of Thinking here is primarily to run tasks and make identifications. ESFPs and INFJs get into a rolling process of making judgments until they reach their conclusions.

Codec dominant (or Judging) types like ENTJs and ISTPs, on the other hand, are more balanced with a good sense of using both Te and Ti. Their main trait, in constrast to the Lens dominant types, is that they're focused on the result--the end product. They're much more head strong with how the outcome should be. As system managers, they seek deterministic explanations and precise outcomes to maintain the order they want. Any deviation from their expectations must have a rationalization.

Understanding the dynamics of Te and Ti helps us appreciate how extraverts and introverts process information and make decisions. Extraverts react and adapt quickly, learning from experience. Introverts anticipate and plan, aiming for precision. Both approaches are vital for navigating the complexities of life and achieving a deeper understanding of the world.

Types in themselves are extremes as well. They exist for the sake of contrast, when we’re much more nuanced in reality, being blends of both Codec and Lens dominant types.