FROM: In 1947, Murray Leinster put on his thinking cap: BrainFi Gets in Your Head

The book really takes on two topics: first contact and the police state. 

Jim Hunt is a scientist who has been experimenting with transmitting thought. This gets him in trouble with the Security Police, who basically rule the world. They keep everything safe. 

Just as Hunt escapes, a spaceship lands just where he happened to get away from the Security Police. It lands unobserved. 

Soon Hunt notices that people are acting very strangely. They all seem strangely run down too. It turns out that they have all joined a hivemind created by alien invaders. 

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