Frege's Theory of Sense and Reference

Frege's theory distinguishes between the "sense" and "reference" of a term. The "sense" is the way a term presents its meaning—the cognitive concept or mental image it evokes—while the "reference" is the actual object or entity the term points to in the real world. For example, "the morning star" and "the evening star" have different senses (different ways of presenting these planets) but the same reference (the planet Venus). This distinction helps explain how statements can be true or false even when different words refer to the same object, based on their different senses.