What is the most fundamental form of thought? In Tibetan Buddhism, there is the concept of the Three Vajras, or The Three Doors, which are body, speech, and mind. The human mind can be said to think in the sensory world (sight, sound, taste, touch, smell), to think in recollections of memories from the past (which is still a sensory experience), and to think in the conjured content of the imagination untouched by memory. These emanations express themselves through the verbal language of speech (which is still a sensory experience of sound; vocal intonations, pitch, rhythm, etc…), and through the non-verbal language of the body (which is still a sensory experience of sight; posture, gestures, eye contact, facial expressions, etc…) Is thought fundamentally empirical, linguistic, emotional, rational, instinctive, or something else entirely? For example: When people think in images, are they really rooted in words; or when people speak in words, they are rooted in i...