PURPOSE: To easily produce each membership function value by setting a contact point for each resistance line at a position between the resistance line and its corresponding lead wire and taking the voltage via each lead wire through a voltage take- out part in accordance with the position of each contact point.

CONSTITUTION: Plural resistance lines 3 are set in parallel with each other on the surface of a base board 1. The both ends of these lines 3 are bundled together and a power supply terminal 4 is attached at one of both ends of the bundle for impression of the power supply voltage together with an earth terminal 5 attached at the other end for connection to the earth. While plural lead wires 6 are set in parallel with each other on the surface of a base board 2 at the same intervals are those of lines 3. An output terminal 7 is set at one of two ends of each wire 6 for take-out of the voltage. A coating layer 10 of an insulated substance is formed on the surface of the board 1 including the lines 3. Then both boards 1 and 2 are put together with their surfaces containing the lines 3 and the wires 6 set opposite to each other in response to the membership value. Thus the conduction is secured between the lines 3 and the wires 6. When the voltage is impressed between both terminals 4 and 5, the voltage equivalent to the membership value is generated at each contact point 8 and its function 9 is obtained.