Here is a list of concepts appearing in Bongard Problems. For bigger-picture categorizations of Bongard Problems, see keywords.

Concept		Meta page	Search
0		See zero	concept:zero
1		See one	concept:one
2		See two	concept:two
2 inputs 1 output		BP906	concept:2_inputs_1_output
3		See three	concept:three
3d front back	P	BP639	concept:3d_front_back
3d impossible solid		BP722	concept:3d_impossible_solid
3d net		BP723	concept:3d_net
3d solid		BP724	concept:3d_solid
4		See four	concept:four
5		See five	concept:five
above below		BP578	concept:above_below
absence as presence	P	BP580	concept:absence_as_presence
absolute direction		BP737	concept:absolute_direction
absolute position	P	BP581	concept:absolute_position
acceleration		BP583	concept:acceleration
acute		BP579	concept:acute
adjacent	P	BP585	concept:adjacent
all	P	BP588	concept:all
analogy		BP584	concept:analogy
angle	P	BP587	concept:angle
antipodal		BP619	concept:antipodal
approximately		See imperfection_small	concept:imperfection_small
area		BP936	concept:area
arrow		BP586	concept:arrow
average	P	BP589	concept:average
background		BP594	concept:background
base		BP590	concept:base
belongs	P	See categorization	concept:categorization
between	P	BP595	concept:between
big	P	See size	concept:size
black white inversion		BP1106	concept:black_white_inversion
bongard problem		BP598	concept:bongard_problem
bounding box	P	BP596	concept:bounding_box
bounding box corner		BP611	concept:bounding_box_corner
bp solution		BP665	concept:bp_solution
branch point		BP597	concept:branch_point
center		BP728	concept:center
center bounding box		BP725	concept:center_bounding_box
center of circle		BP726	concept:center_of_circle
center of mass		BP727	concept:center_of_mass
chess-like		BP599	concept:chess-like
choice		BP980	concept:choice
circle		BP526	concept:circle
close to		See near_far	concept:near_far
closed open	P	BP603	concept:closed_open
cluster	P	BP733	concept:cluster
cluster barycenter		BP591	concept:cluster_barycenter
cluster of one		BP732	concept:cluster_of_one
collinear	P	BP604	concept:collinear
collision		BP857	concept:collision
color	P	See outlined_filled	concept:outlined_filled
completed out of box	P	BP613	concept:completed_out_of_box
completeness		BP605	concept:completeness
concave convex angle		BP607	concept:concave_convex_angle
concave convex region	P	BP606	concept:concave_convex_region
conjunction logical	P	See and	concept:and
connected component		BP1236	concept:connected_component
continuous change	P	See discrete_continuous	concept:discrete_continuous
contrast		BP612	concept:contrast
convex hull	P	BP610	concept:convex_hull
convey enough information		BP916	concept:convey_enough_information
coordinate	P	BP609	concept:coordinate
correspondence	P	BP615	concept:correspondence
counting	P	See iteration	concept:iteration
cross section		BP817	concept:cross_section
cube		BP1103	concept:cube
curved straight	P	BP617	concept:curved_straight
curve texture		BP761	concept:curve_texture
cusp		BP614	concept:cusp
cyclic path		BP618	concept:cyclic_path
decreasing	P	See size_increase_decrease	concept:size_increase_decrease
diagonal		BP1234	concept:diagonal
dimensionality	P	BP622	concept:dimensionality
direction	P	BP807	concept:direction
disjunction logical	P	See or	concept:or
disorder	P	See pattern_or_random	concept:pattern_or_random
distance from center		BP819	concept:distance_from_center
distinguishing crossing curves		BP1235	concept:distinguishing_crossing_curves
division		BP624	concept:division
dot	P	BP679	concept:dot
downward upward		BP625	concept:downward_upward
element wise symmetry		BP1186	concept:element_wise_symmetry
elongated compact	P	BP626	concept:elongated_compact
entrance exit		BP630	concept:entrance_exit
entropy	P	See pattern_or_random	concept:pattern_or_random
equilateral triangle		BP764	concept:equilateral_triangle
every other		BP632	concept:every_other
exclusive or logical operator		See xor	concept:xor
existence	P	BP634	concept:existence
exists one		BP635	concept:exists_one
exponential		BP636	concept:exponential
extra part		BP815	concept:extra_part
far from		See near_far	concept:near_far
feature cluster		BP729	concept:feature_cluster
fewer		See quantity_comparison	concept:quantity_comparison
filled	P	See outlined_filled	concept:outlined_filled
fractal		BP638	concept:fractal
fraction	P	See ratio	concept:ratio
function		BP918	concept:function
gear		BP642	concept:gear
ghost		BP640	concept:ghost
golden ratio		BP800	concept:golden_ratio
graph		BP1023	concept:graph
gravity		BP921	concept:gravity
greater		See quantity_comparison	concept:quantity_comparison
greater than		See quantity_comparison	concept:quantity_comparison
half		BP644	concept:half
hole	P	BP641	concept:hole
horizontal		BP645	concept:horizontal
identical		BP643	concept:identical
iff		BP647	concept:iff
imagined entity	P	BP741	concept:imagined_entity
imagined line or curve		BP739	concept:imagined_line_or_curve
imagined motion		BP742	concept:imagined_motion
imagined point		BP738	concept:imagined_point
imagined shape		BP740	concept:imagined_shape
impossible		BP1134	concept:impossible
increasing	P	See size_increase_decrease	concept:size_increase_decrease
infinite plane		BP648	concept:infinite_plane
infinity	P	See finite_infinite	concept:finite_infinite
innermost outermost		BP649	concept:innermost_outermost
inside	P	BP651	concept:inside
interior exterior	P	BP652	concept:interior_exterior
intersection	P	See x-crossing	concept:x-crossing
intersection	P	See overlap	concept:overlap
isosceles triangle		BP766	concept:isosceles_triangle
jigsaw puzzle		BP656	concept:jigsaw_puzzle
knot		BP655	concept:knot
large	P	See size	concept:size
larger, becoming	P	See size_increase_decrease	concept:size_increase_decrease
leftward rightward		BP658	concept:leftward_rightward
left right	P	BP657	concept:left_right
length line or curve	P	BP659	concept:length_line_or_curve
less		See quantity_comparison	concept:quantity_comparison
less than		See quantity_comparison	concept:quantity_comparison
lesser		See quantity_comparison	concept:quantity_comparison
light dark	P	BP662	concept:light_dark
lines coincide		BP602	concept:lines_coincide
line absolute direction		BP734	concept:line_absolute_direction
line or curve endpoint	P	BP629	concept:line_or_curve_endpoint
line slope	P	BP701	concept:line_slope
liquid flow		BP808	concept:liquid_flow
local global		BP1244	concept:local_global
local max min		BP663	concept:local_max_min
loop	P	BP661	concept:loop
maze		BP664	concept:maze
mentally remove object	P	BP688	concept:mentally_remove_object
midpoint		BP667	concept:midpoint
missing part		BP668	concept:missing_part
more		See quantity_comparison	concept:quantity_comparison
most		BP982	concept:most
motion	P	BP744	concept:motion
multiple of		BP670	concept:multiple_of
neck narrowing		BP671	concept:neck_narrowing
nesting	P	See recursion	concept:recursion
notch	P	See indentation	concept:indentation
nothing	P	See empty	concept:empty
number	P	BP672	concept:number
number cluster		BP730	concept:number_cluster
numerosity		BP673	concept:numerosity
objects overlap		BP745	concept:objects_overlap
object line overlap		BP746	concept:object_line_overlap
odd		See even_odd	concept:even_odd
on line or curve	P	BP660	concept:on_line_or_curve
on sides of curve	P	BP689	concept:on_sides_of_curve
order	P	See pattern_or_random	concept:pattern_or_random
ordinal orering	P	BP674	concept:ordinal_orering
outer outline		BP675	concept:outer_outline
overlapping	P	See overlap	concept:overlap
parallel		BP984	concept:parallel
path	P	BP677	concept:path
percentage	P	See ratio	concept:ratio
perimeter		BP938	concept:perimeter
permutation		BP923	concept:permutation
perpendicular		BP985	concept:perpendicular
physically fitting		BP890	concept:physically_fitting
plus		See addition	concept:addition
pointing to	P	BP683	concept:pointing_to
positive negative slope		BP700	concept:positive_negative_slope
prime		BP682	concept:prime
product		BP910	concept:product
projection		BP901	concept:projection
proportional	P	BP681	concept:proportional
protrusion	P	BP680	concept:protrusion
reachable		BP685	concept:reachable
real motion		BP743	concept:real_motion
recursion number		BP1020	concept:recursion_number
regular irregular change	P	BP686	concept:regular_irregular_change
rigid		See rigidity	concept:rigidity
rotational direction		BP736	concept:rotational_direction
rotational symmetry		BP759	concept:rotational_symmetry
rotation required	P	BP690	concept:rotation_required
same	P	BP752	concept:same
same concept		BP751	concept:same_concept
same feature		BP748	concept:same_feature
same number		BP749	concept:same_number
same shape		BP750	concept:same_shape
self-reference	P	BP691	concept:self-reference
semidecidable		BP1078	concept:semidecidable
separable entangled		BP693	concept:separable_entangled
separated regions		BP1021	concept:separated_regions
separation of joined objects	P	BP692	concept:separation_of_joined_objects
sequence		BP697	concept:sequence
set intersection	P	BP653	concept:set_intersection
set union	P	BP713	concept:set_union
shape background	P	BP593	concept:shape_background
shape cluster		BP731	concept:shape_cluster
sides of line	P	BP694	concept:sides_of_line
similar		BP757	concept:similar
similar feature		BP753	concept:similar_feature
similar number		BP754	concept:similar_number
similar representation		BP756	concept:similar_representation
similar shape		BP755	concept:similar_shape
simplicity		BP695	concept:simplicity
slope at endpoint		BP628	concept:slope_at_endpoint
small	P	See size	concept:size
smaller, becoming	P	See size_increase_decrease	concept:size_increase_decrease
specificity	P	BP773	concept:specificity
specific shape		BP770	concept:specific_shape
specific style		BP771	concept:specific_style
specific value		BP772	concept:specific_value
speed	P	BP698	concept:speed
square		BP699	concept:square
square number		BP702	concept:square_number
statistical variance	P	BP715	concept:statistical_variance
subtraction		BP620	concept:subtraction
sum		See addition	concept:addition
symmetry	P	BP760	concept:symmetry
symmetry axis		BP758	concept:symmetry_axis
t-crossing	P	See t-point	concept:t-point
tangent	P	BP703	concept:tangent
tangent absolute direction		BP735	concept:tangent_absolute_direction
tessellation		BP704	concept:tessellation
texture	P	BP763	concept:texture
texture area		BP762	concept:texture_area
tiling		BP706	concept:tiling
together		See near_far	concept:near_far
topological density		BP1117	concept:topological_density
topological transformation		BP705	concept:topological_transformation
tracing lines or curves meet	P	BP666	concept:tracing_lines_or_curves_meet
tracing line or curve	P	BP708	concept:tracing_line_or_curve
triangle		BP769	concept:triangle
triangle arrow		BP768	concept:triangle_arrow
triangle incenter		BP765	concept:triangle_incenter
triangle orthocenter		BP767	concept:triangle_orthocenter
true false	P	BP709	concept:true_false
trunk of tree		BP710	concept:trunk_of_tree
tumbles or stays put		BP712	concept:tumbles_or_stays_put
turning direction		BP711	concept:turning_direction
turn orientation		BP601	concept:turn_orientation
uppermost lowermost		BP714	concept:uppermost_lowermost
vertex of meeting lines	P	BP716	concept:vertex_of_meeting_lines
vertical		BP804	concept:vertical
visual disparity	P	See 3d_depth	concept:3d_depth
visual illusion		BP717	concept:visual_illusion
wave		BP721	concept:wave
wrapping around bounding box		BP720	concept:wrapping_around_bounding_box
write in single stroke		BP718	concept:write_in_single_stroke
x-point	P	See x-crossing	concept:x-crossing