“Why || “But why do you speak both of physical & mental ‘strain’?” – “Because they have a certain similarity, they have a common element.” What is this common element? Can you point to it as you pointed in …? Can you say anything more about it than that it is the element of strain? ¤
     “It is a certain tension.” That doesn't get us any further, for why do you talk of tension in these different cases.
     “A certain feeling of tension accompanies || is part of both experiences”. Are you not just translating what you said before, into other language or are you actually referring to an experience like that of feeling your heart beat. Thus I could || , as you could say that this feeling is a constituent both of certain sensations of fear & of hopes || joy.