---

       # MATH introduce the AND logical operator
[hear] (intro and);

[hear] (define and
          (? x /
           ? y /
           if (x) (if (y) (true) (false)) (false)));

[hear] (and (= 0110 0110) (> 011110 0110));

[hear] (and (= 010 010) (> 01111110 011110));

[hear] (and (< 01110 011110) (= 0111110 0111110));

[hear] (and (= 01110 01110) (= 011110 011110));

[hear] (and (= 01110 01110) (= 00 00));

[hear] (and (< 0111110 011111110) (> 0111110 01110));

[hear] (and (> 0111110 011110) (> 010 00));

[hear] (and (> 01110 00) (= 01110 01110));

[hear] (and (< 01110 011110) (< 01110 01111110));

[hear] (and (> 0111110 011110) (> 0111110 011110));

[hear] (not / and (> 01111110 011110) (< 01110 010));

[hear] (not / and (> 01110 010) (> 01110 01110));

[hear] (not / and (= 00 00) (= 0111110 011110));

[hear] (not /
         and (< 0110 011110) (> 011110 01111110));

[hear] (not / and (= 01110 01110) (= 01110 010));

[hear] (not /
         and (> 010 0111110) (< 01110 01111110));

[hear] (not / and (< 01111110 0110) (= 0110 0110));

[hear] (not /
         and (> 0110 0111110) (= 0111110 0111110));

[hear] (not / and (< 01111110 0110) (= 01110 01110));

[hear] (not / and (< 011110 01110) (> 0111110 0110));

[hear] (not / and (< 0111110 011110) (= 010 0110));

[hear] (not /
         and (< 01111110 011110) (= 0111110 010));

[hear] (not / and (> 0110 01111110) (= 010 0111110));

[hear] (not / and (< 01111110 01110) (= 0110 01110));

[hear] (not / and (< 01111110 011110) (> 00 010));

[hear] (not / and (= 01110 0111110) (< 011110 010));

[hear] (not / and (= 011110 010) (< 011110 0110));

[hear] (not / and (< 01111110 01110) (= 01110 00));

[hear] (not /
         and (< 011110 0110) (< 011110 01111110));

[hear] (not / and (> 011110 010) (< 0111110 0110));

[hear] (not / and (> 00 010) (> 011111110 0111110));

[hear] (not /
         and (< 01110 011110) (> 01110 01111110));

[hear] (not / and (> 010 0110) (> 01111110 011110));

[hear] (not / and (< 00 010) (= 011110 0111110));

[hear] (and (< 011110 01111110) (< 0111110 011111110));