A1 Common sense
C1 Wordsymth: practical judgment based on experience or native intelligence, and not on education or training.
C2 Infoplease: sound practical judgment that is independent of specialized knowledge, training, or the like; normal native intelligence. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.
C3 The Law Dictionary: Sound practical judgment; that degree of intelligence and reason, as exercised upon the relations of persons and things and the ordinary affairs of life, which is possessed by the generality of mankind, and which would suffice to direct the conduct and actions of the individual in a manner to agree with the behavior of ordinary persons.
C4 Sense can be both
D1 Common in that people and animals recognize a certain shape, smell, taste, etc. to be the same. Salt is an example.
D2 Special in that people know their culture and cultural thinking, which would influence a decision or opinion.
C1 We don't step in front of a speeding car, because we know what will happen. We have seen pictures of it, etc.
C2 We don't drink poison, because we know what poison does.
A2 Atheist explanation
B1 Some may consider common sense true, but it really might not be. It used to be people considered tomatoes poisonous, but obviously they are not.
B2 Our common sense may reject things that we cannot see or experience but are in fact true as the movement of continental plates or a heavy and light object fall at the same rate (resistance as air, etc. influences the slower fall of feathers compared to a rock).
B1 Christians have a reasonable faith, not a common sense faith (even if that is true).
B2 Christians appeal to facts as history, archeology, and the great number of eye witnesses.
B3 People may have different philosophical definitions of truth, but when they are short-changed by the cashier, they throw their philosophy out the window and want the correct change back.
B4 Faith is based on truth.
B5 Faith in someone is based on prior dealings with him/her. They are proven.
B6 Jesus existed. This is most reasonable.