For example, I came across one where the pattern can only be seen by identifying opposite edges and viewing the grid as a torus.
If you mean what I think you mean by a torus, that will maintain the vertical and horizontal symmetry. The claim I am confident in is that I don’t think any Raven’s test has two potential answers, one of which is more sensible if you perceive the pattern horizontally and another of which is more sensible if you perceive the pattern vertically. I am not sure whether that is accomplished by there being two equally reasonably concluding items, one of which is not included in the potential answer set, or by there never being two equally reasonable concluding items in the set of all possible items.
The weaker claim, that is mostly speculation, is that the description of the pattern is the same both ways. For example, consider this possibility:
1 0 1
1 0 1
1 0 ?
The answer is obviously 1, but is it because it’s an xor, adding, or multiplication? The first two work horizontally but not vertically, and the latter only works vertically. I don’t think there are many (any?) test patterns that look like that.
If you mean what I think you mean by a torus, that will maintain the vertical and horizontal symmetry. The claim I am confident in is that I don’t think any Raven’s test has two potential answers, one of which is more sensible if you perceive the pattern horizontally and another of which is more sensible if you perceive the pattern vertically. I am not sure whether that is accomplished by there being two equally reasonably concluding items, one of which is not included in the potential answer set, or by there never being two equally reasonable concluding items in the set of all possible items.
The weaker claim, that is mostly speculation, is that the description of the pattern is the same both ways. For example, consider this possibility:
The answer is obviously 1, but is it because it’s an xor, adding, or multiplication? The first two work horizontally but not vertically, and the latter only works vertically. I don’t think there are many (any?) test patterns that look like that.