This extension of the libido theory-in my opinion, a legitimate one- receives rein-forcement from a third quarter, namely, from our observations and views on the mental life of ehil-dren and primitive peoples. in the latter we find characteristics which, if they occurred singly, might be put down to megalomania: an over-estimation of the power of their wishes and mental acts, the `omnipotence of thoughts`, a belief in the thaumaturgic force of words, and a technique for dealing with the external world-`magic`-which appears to be a logical application of these grandi-ose premisses. in the children of to-day, whose development is much more obscure to us, we expect to find an exactly analogous attitude to-wards the external world.