1. A multi-mode sight consisting essentially of: an optical sight that provides a direct view image of an aiming point or reticle superimposed on a target scene; a thermal imager that provides a monochromic thermal image of the target scene; a single, superimposed direct view and thermal optical image path defined through the optical sight; a single combiner in the single, superimposed direct view and thermal optical image path that passes the direct view image and reflects the thermal image such that the thermal image is superimposed onto the direct view image to form a superimposed thermal and direct view optical image of the target scene together with the aiming point or reticle; and a night-vision device positioned at an exit pupil, wherein the night-vision device light-intensifies the superimposed thermal and direct view optical image of the target scene together with the aiming point or reticle for night-time use.