Negative instruction, [250], [253].
[Nerve-forces], directive, [18], [96] f., [164], [205] f., [212] ff.;
in perception and idea, [115] ff.;
of reinforcement and inhibition, in attention, [106] ff., [164], [249] f.;
double-acting, [109], [249] f.;
in memory, [190];
in imagination, [199] f.;
in selective action, [248];
in volitional action, [251];