Let x be a randomly chosen real number in [0,1]. What does it mean to "manipulate x's concept" or "think in terms of x"? Do these phrases attach themselves to

Let x be a randomly chosen real number in [0,1]. What does it mean to "manipulate x's concept" or "think in terms of x"? Do these phrases attach themselves to the real number, or to the expression language? If the latter, do you say two number-expressions are equivalent if applying some normalization function yields two equal expressions? Do you consider two number-expressions distinct if they evaluate to the same real number, but cannot directly be related to each other? For example, let: S = { (x, e^(ix) + 1) | x in R, x > 0 }, T = { x | (x,y) in S, y = 0 }, c1 = min(T), c2 = 6 * sqrt(sum(n^-2, n > 0)) If my memory's right, c1 and c2 evaluate to the same real number which happens to be equal to Pi. What does it mean to manipulate c1's concept or think in terms of it? Does c1 have the same concept as Pi?