Sentence:  The underlying assumption , of course , is that only sight and <WSD>touch</WSD> enable us , in any precise and fully dependable way , to locate objects in space beyond us , the other senses being decidedly inferior , if not totally inadequate , in this regard . 
Meaning of the word marked with <WSD> tags:  the faculty by which external objects or forces are perceived through contact with the body (especially the hands)