A method, system, and recording medium for communication comparison including encrypting a first communication and a second communication, determining a list of frequencies and intensities based on the first communication and the second communication, projecting light based on the list of frequencies and intensities of the first communication onto an object, reading the frequencies and intensities of the light based on the first communication from the object, and comparing the light read in the reading with the list of frequencies and intensities of the second communication to calculate a semantic overlap between the frequencies and intensities of the first communication and the second communication.