Infrared (IR) is a portion of invisible spectrum: the portion of the invisible electromagnetic spectrum consisting of radiation with wavelengths in the range 750 nm () to 1 mm (), between light and radio waves (1). Infrared light was discovered in 1800 by Sir Frederick William Herschel (2). In the last several decades the use of IR cameras and goggles for military, police and civilian purposes has grown. Since our human senses are not capable of perceiving IR light we didn’t even know about it for centuries. Does this mean that IR light didn’t exist prior to 1800? Of course not! We just couldn’t see it. However, this is precisely what skeptics say about the spiritual world; that because we can’t see it, it doesn’t exist. What if the spiritual world like, IR light prior to 1800, exists but we just don’t the means to see it via our senses or current technology?
1. Encarta® World English Dictionary[North American Edition]