Panels on the left hand side contain geometrical objects that appear distorted (to a human) due to surrounding information.

Vicente Sierra-Vázquez & Ignacio Serrano-Pedraza, Application of Riesz transforms to the isotropic AM-PM decomposition of geometrical-optical illusion images, April 2010, Figure 1.

Adjacent-numbered pages:
BP934 BP935 BP936 BP937 BP938  *  BP940 BP941 BP942 BP943 BP944

fuzzy, anticomputer, subjective, contributepairs, invalid, experimental

Leo Crabbe

Left-sorted Problems have the keyword "right-listable" on the OEBP.

BPs are sorted based on how BP563 (left-listable) would sort them were they flipped; see that page for a description.

See right-finite, which distinguishes between finite right side and infinite right side.

Adjacent-numbered pages:
BP935 BP936 BP937 BP938 BP939  *  BP941 BP942 BP943 BP944 BP945

meta (see left/right), links, keyword

bp_infinite_right_examples [smaller | same | bigger]
zoom in right (right_uncountable_bp)

Leo Crabbe

Evidently this solution is stretching the idea of what makes images "different". Each corresponding pair of panels would be parsed as identical in any other case. It is worth noting that if you view this Problem on a template, the solution no longer applies at all.

Adjacent-numbered pages:
BP936 BP937 BP938 BP939 BP940  *  BP942 BP943 BP944 BP945 BP946

less, precise, dual, antihuman, contributepairs, invalid, experimental, funny

Leo Crabbe

Adjacent-numbered pages:
BP937 BP938 BP939 BP940 BP941  *  BP943 BP944 BP945 BP946 BP947

precise, stretch, boundingbox, invalid, experimental, preciseworld

rectangular_arrangement_of_white_pixels [smaller | same | bigger]
zoom in left (square_arrangement_of_white_pixels) | zoom in right (oblong_rectangular_arrangement_of_white_pixels)

Leo Crabbe

Left examples are not required to be valid, as long as their solution doesn't apply in the traditional Bongard Problem format (6 panels vs. 6 panels, all one image). Additionally, they do not necessarily have to be rendered invalid by being viewed in the template format, but their solution does have to be altered. In some cases left examples are simply Problems whose solution is specific to the computer medium (BP941), however some examples have more profound solutions that the pen-and-paper template medium is too restrictive to represent (BP854).

See BP568.

Adjacent-numbered pages:
BP938 BP939 BP940 BP941 BP942  *  BP944 BP945 BP946 BP947 BP948

meta (see left/right), links, oebp, time

bp [smaller | same | bigger]

Leo Crabbe

"Any" here means any image of a Bongard Problem in the relevant format, i.e. with white background, black vertical dividing line, and examples in boxes on either side.

All examples shown in this Problem clearly sort themselves on the left or right.

A self-referential but maybe simpler solution is "would sort all examples in this whole Bongard Problem on one of its sides vs. not so." Users adding examples please try to maintain this: for any example you add to the right of this Bongard Problem, make sure it does not sort all the other examples in this Bongard Problem on just one of its sides. - Aaron David Fairbanks, Aug 26 2020

Adjacent-numbered pages:
BP939 BP940 BP941 BP942 BP943  *  BP945 BP946 BP947 BP948 BP949

hard, challenge, presentationinvariant

boxes_bpimage_sorts_self [smaller | same | bigger]
zoom in left | zoom in right

Jago Collins

Adjacent-numbered pages:
BP940 BP941 BP942 BP943 BP944  *  BP946 BP947 BP948 BP949 BP950

precise, allsorted, number, left-null, help, preciseworld

dots [smaller | same | bigger]

Leo Crabbe

"Full overlapping not allowed" means you cannot overlay an image onto itself without moving it; if this were allowed all images would be sorted on the left. The copies can be moved around (translated) in 2D but can not be flipped or rotated.

There are examples on the right drawn with thick lines, and these could be created by copying an image with slightly thinner lines and moving it over a tiny amount. If you fix this issue by saying "the copy has to be moved over more than a tiny amount" then the Bongard Problem is perfect but not precise, but if you fix this issue by saying "interpret the figures as made up of (infinitesimally) thin lines" then it's precise but not perfect. - Aaron David Fairbanks, Jun 17 2023

Adjacent-numbered pages:
BP941 BP942 BP943 BP944 BP945  *  BP947 BP948 BP949 BP950 BP951

nice, notso, creativeexamples

Leo Crabbe

Left examples have the keyword "pixelperfect" on the OEBP.

All examples here are perfect Bongard Problems. That is, subtle imperfections in images are meant to be considered.

When a Problem is tagged with "pixelperfect", users are reminded to make sure they do not upload images such that taking the pixelation into account would affect the sorting of that example. That is, the zoomed-in jagged blocky version of the picture should still fit the solution.

For example, in the examples of BP335, which is about tessellation, the pixels interlock properly.

Stable Bongard Problems are generally pixelperfect.

Adjacent-numbered pages:
BP942 BP943 BP944 BP945 BP946  *  BP948 BP949 BP950 BP951 BP952

meta (see left/right), links, keyword, instruction

perfect_bp [smaller | same | bigger]

Leo Crabbe

See BP556 (keyword blackwhite) for the version with links to pages on the OEBP instead of images of Bongard Problems.

Adjacent-numbered pages:
BP943 BP944 BP945 BP946 BP947  *  BP949 BP950 BP951 BP952 BP953

meta (see left/right), miniproblems, presentationinvariant

Leo Crabbe