Let's assume we would agree that all people under 1.70m are definitely not tall, and all people over 1.90m are definitely tall. Then we could draw the following "fuzzy" function G(x):
So we have solved the problem of the sharp border between "big" and "not big" by creating a smooth transition. The transition is not vertical, as with the "sharp" sets, but has a more or less pronounced gradient. The transition is linear (one line). We could also have taken any nonlinear curve. Because of the complex calculation of nonlinear transitions, in practice the fuzzy membership functions are modeled from lines.
