Which of the following is NOT considered a type of personal knowledge?

Personal knowledge typically refers to the information and understanding an individual has acquired through direct experience, sensory perception, or interactive engagement with their environment. Observations and touch are integral components of personal knowledge; they involve direct sensory experiences that contribute to an individual's understanding.

In contrast, speculations involve conjectures or assumptions that are not grounded in direct experience. They are based on possibilities and theoretical knowledge rather than firsthand information. Therefore, while observations and touch are concrete and derive from personal interaction with the world, speculations do not fit this definition as they do not rely on direct sensory experience or factual evidence.

Physical evidence, while crucial in investigative contexts, refers to tangible items that can be used to support claims or conclusions. It is also distinct from personal knowledge in that it is not derived from the individual's personal experiences but rather from external sources.

Thus, speculations stand out as not being a type of personal knowledge because they lack the foundation of firsthand experience that characterizes the other options.