If the standard hydrogen electrode (SHE) is set arbitrarily to have a potential that is equal to 0 V, and has an absolute real potential. Then, in electrochemistry, how are the electrode potentials of other electrodes are determined using it?

Our high school textbook states that we form a galvanic cell from the SHE and another half cell of the electrode that we want to determine its potential. Then using the voltmeter, the voltage of the cell should resemble the standard electrode potential of the electrode.

I really don’t get it, because the voltage should resemble the difference in potential between the electrodes.

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    $\begingroup$ True, the voltage is the difference; what's unclear about that? $\endgroup$ – Ivan Neretin Apr 25 '19 at 11:21
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    $\begingroup$ Exactly as you described. $\endgroup$ – Ivan Neretin Apr 25 '19 at 11:52
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    $\begingroup$ We are not determining the "absolute real" potentials of the other half cells, either. It's just like elevation about sea level. Mount Everest (सगरमाथा or ཇོ་མོ་གླང་མ) is not 8,848 m tall in absolute terms (not sure what that would be, from the center of the earth or how high you have to climb from the closest bus stop), it is 8,848 m higher than the sea level. As sea levels are rising, Mount Everest will shrink. $\endgroup$ – Karsten Theis Apr 25 '19 at 12:25
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    $\begingroup$ I think I wrote a relevant answer for a slightly different question: chemistry.stackexchange.com/questions/112316/… $\endgroup$ – Zhe Apr 25 '19 at 13:31
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    $\begingroup$ You can only measure the voltage of a cell. $\ce{V_{cell} = V_{cathode} − V_{anode}}$. The SHE arbitrarily has $\ce{V_{anode} = 0}$. So all other half cells are measured relative to it. // LOL - Remember Einstein "everything is relative..." $\endgroup$ – MaxW Apr 25 '19 at 16:14

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