Ruyer, La cybernétique et l’origine de l’information, 1954

1. Calculating machines: simple information machines used for adding, subtracting, multiplication, division and other calculations.

2. Reasoning machines: algebraic machines where variables include, importantly, truth values (true and false), denoted in binary.

3. Inducing machines: machines that perform statistical inference, or machine learning.

4. Auto-regulating machines: machines with the capability of adjusting their actions according to feedback mechanisms.