What sensory perceptions establish the knowledge required for valid testimony?

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The established means of knowledge that validate testimony are two: sight (seeing) and hearing (listening). Other means of knowledge, such as smell, taste, and touch, are generally not required for testimony. Testimony based on sight applies to actions, such as usurpation, destruction, fornication, and drinking wine, as well as visible attributes, such as defects in a sold item. Testimony regarding these matters requires sight because it allows for definitive confirmation, precluding reliance on other means.